Barium – 122 has a half-life of 2 minutes. Suppose you obtain a sample weighing 10.0 g and it takes 10 minutes to set up an experiment. How many grams of Barium – 122 will remain at the point when you begin the experiment

Answers

Answer 1

Answer:

0.3125 g

Explanation:

Given data:

Half life of barium-122 = 2 min

Mass of sample = 10.0 g

Mass of barium remain after 10 min = ?

Solution:

Number of half lives = Time elapsed / half life

Number of half lives = 10 min/ 2 min

Number of half lives = 5

At time zero = 10 g

At 1st half life = 10 g/2 = 5 g

At 2nd half life = 5 g/2 = 2.5 g

At 3rd half life = 2.5 g/2 = 1.25 g

At 4th half life = 1.25 g/2 = 0.625 g

At 5th half life = 0.625 g/2 = 0.3125 g


Related Questions

Which of the following favors the solubility of an ionic solid in a liquid solvent? Group of answer choices a large magnitude of the solvation energy of the ions a small magnitude of the lattice energy of the solute a large polarity of the solvent all of the above none of the above

Answers

Answer:

all of the above

Explanation:

The solubility of an ionic solid in a liquid solvent largely depends on three factors:

i) The solvation energy

ii) The lattice energy of the solid

iii) The polarity of the of the solvent

A large solvation energy and a small magnitude of lattice energy means that the ionic solute will dissolve very easily in the solvent.

Secondly, the solvent must have a large polarity, this is why water serves as a good solvent for most ionic solutes.

smallest to largest: mountain system, mountain range, mountain belt, mountain.

Answers

Mountain ,mountain range ,mountain system ,mountain belt

Answer:

mountain, mountain range, mountain system, mountain belt

Explanation:

edge 2021

A 50.0 g sample of an unknown substance, initially at 20.2 °C, was heated with 1.55 kJ of energy. The final temperature of the substance was 125.0 °C. Determine the specific heat of this substance.

Answers

Answer:

0.296j/g⁰c

Explanation:

we have the following information from this question before us.

mass iv substance = 50grams

we have initial temperature ti = 20.2c

final temperature = 125c

the energy that was provided = 155kj

we proceed with this formula

energy = mcΔT

1.55x10³ = 50 x c x (125-20.2)

1.55x10³ = c x 50gm x 104.8k

we divide through to get c

c = 1.55x1/50g x 104.8

c = 0.296J/g⁰c

that is the specific heat of this substance.

thank you!

A. Express each Fraction in Decimal form. Round off your answers into
thousandths place.
1. 3/4​

Answers

Answer:

0.75

Explanation:

3/4=0.75 so therefore its 0.75


A boiling pot of soup with a lid on it to keep in the energy is what type of system?
open
closed
isolated
none of the above

Answers

Answer: In a closed system, only energy can be exchanged between the system and the surroundings. In the same example of boiling a pot of water, putting the lid on the system changes it from open to closed. This is because when the lid is on the pot, matter can no longer escape.

Explanation:

Answer:

I think its closed

Explanation:

Sorry if its wrong

Which of the following is an Elementary compound?

A. CO2

B. N2

C. SO2

D. H2S


heeeeeeeeeelp please please please ​

Answers

Answer:

Explanation:

In my opinion the answer should be SO2

Answer:

a should be answer i think.

1.547 grams of hydrated MgSO4 is heated in a crucible. After heating, 0.7554 grams of anhydrous MgSO4 remains in the crucible. How many waters of hydration were attached to the MgSO4

Answers

Answer:

7

Explanation:

Let x represent the number of moles of water in the hydrated salt i.e MgSO₄.xH₂O

The following data were obtained from the question:

Mass of MgSO₄.xH₂O = 1.547 g

Mass of anhydrous MgSO₄ = 0.7554 g

Mole of H₂O = x =?

Next, we shall determine the mass of water, H₂O in the hydrated salt, MgSO₄.xH₂O. This can be obtained as follow:

Mass of MgSO₄.xH₂O = 1.547 g

Mass of anhydrous MgSO₄ = 0.7554 g

Mass of H₂O =?

Mass of H₂O = (Mass of MgSO₄.xH₂O) – (Mass of anhydrous MgSO₄)

Mass of H₂O = 1.547 – 0.7554

Mass of H₂O = 0.7916 g

Finally, we shall determine the value of the x as illustrated below:

Mass of MgSO₄.xH₂O = 1.547 g

Molar mass of MgSO₄.xH₂O = 24 + 32 + (16×4) + x[(2×1) + 16]

= 24 + 32 + 64 + x(2 + 16)

= 120 + 18x

Mass of H₂O = 0.7916 g

Molar mass of xH₂O = 18x

Molar Mass of xH₂O/ Molar mass of MgSO₄.xH₂O = mass of xH₂O /Mass of MgSO₄.xH₂O

18x/ 120 + 18x = 0.7916/1.547

Cross multiply

0.7916 (120 + 18x) = 18x × 1.547

94.992 + 14.2488x = 27.846x

Collect like terms

94.992 = 27.846x – 14.2488x

94.992 = 13.5972x

Divide both side by 13.5972

x = 94.992 / 13.5972

x = 7

Thus, the formula for the hydrated salt, MgSO₄.xH₂O is MgSO₄.7H₂O

Number of moles of water, H₂O in the hydrated salt MgSO₄.7H₂O is 7.

The number of moles of attached water molecules is 7.

Mass of hydrated MgSO4 = 1.547 grams

Mass of anhydrous MgSO4 = 0.7554 grams

Number of moles of hydrated MgSO4 = 1.547 grams/120 + 18x

Number of moles of anhydrous MgSO4 = 0.7554 grams /120

Number of moles of anhydrous salt = Number of moles of hydrated salt

0.7554 grams /120 = 1.547 grams/120 + 18x

0.7554(120 + 18x) = 1.547 × 120

90.6 + 13.6x = 185.6

185.6 - 90.6 /13.6 = x

x = 7

The number of moles of attached water molecules is 7.

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The density for potassium is 0.856 g/cm3. What would be the mass of a 35 cm3 piece of potassium?

Answers

Answer:

30 grams

Explanation:

density = mass / volume => mass = density x volume

mass = 0.856 g/cm³  x  35 cm³ = 29.96 grams ≅ 30 grams 2 sig. figs.  

List the following elements in order of INcreasing number of valence electrons: C, Cl, As, Na, He

Answers

Answer:

He, Cl, As, C, Na

Explanation:

^^

A student dissolves of sodium hydroxide in of water in a well-insulated open cup. He that observes the temperature of the water rise from to over the course of minutes. Use this data, and any information you need from the ALEKS Data resource,
NaOH(s) rightarrow Na+(aq) + OH-(aq)
You can make any reasonable assumptions about the physical properties of the solution. Note for advanced students: it's possible the student did not do the experiment carefully, and the values you calculate may not be the same as the known and published values for this reaction.
1. Is this reaction exothermic, endothermic, or neither.
2. If you said the reaction was exothermic or endothermic, calculate the amount of neat that was released or absorbed by the reaction in this case.
3. Calculate the reaction enthalpy AW per mole of NaOH.

Answers

Answer:

This question is incomplete

Explanation:

This question is incomplete but the answer to (1) and steps involved in calculating (2) and (3) will be discussed in the attachment

1. The reaction is an exothermic reaction because heat was given off. Exothermic reaction is a reaction in which heat is released from a reaction into the surroundings. And according to the question, the student observed that the temperature of the water increased during the course of the minutes.

The indicator dilution method is a technique used to determine flow rates of fluids in channels for which devices like rotameters and orifice meters cannot be used (e.g., rivers, blood vessels, and large- diameter pipelines). A stream of an easily measured substance (the tracer) is injected into the channel at a known rate and the tracer concentration is measured at a point far enough downstream of the injection point for the tracer to be completely mixed with the flowing fluid. The larger the flow rate of the fluid, the lower the tracer concentration at the measurement point. A gas stream that contains 1.50 mole% CO2 flows through a pipeline, Twenty (20.0) kilograms of CO2 per minute is injected into the line. A sample of the gas is drawn from a point in the line 150 meters downstream of the injection point and found to contain 2.3 mole% CO2.(a) Estimate the gas flow rate (k mol/min) upstream of the injection point.(b) Eighteen seconds elapses from the instant the additional CO2 is first injected to the time the CO2 concentration at the measurement point begins to rise. Assuming that the tracer travels at the average velocity of the gas in the pipeline (i.e., neglecting diffusion of CO2), estimate the average velocity (m/s), if the molar gas density is 0.123k mol/m3 what is the pipe diameter?

Answers

Answer:

[a]. 55.5kmol/min.

[b]. The average velocity = 8.3m/s.

pipe diameter = 1.0954m.

Explanation:

So, from the question above we are given the following data or information or parameters which are going to help us in solving the above question;

=> ''A gas stream that contains 1.50 mole% CO2 flows through a pipeline''

=> ''Twenty (20.0) kilograms of CO2 per minute is injected into the line.''

=> '' . A sample of the gas is drawn from a point in the line 150 meters downstream of the injection point and found to contain 2.3 mole% CO2''

=> ''molar gas density is 0.123k mol/m3''

[a].The gas flow rate (k mol/min) upstream of the injection point can be calculated as follows.

- Determine the mass balance= j₁ +[ 20 /.123 × 44] = j₃. Thus, the flow gas rate is given as;

w₁ ×  1.50 mole% CO2 + 3.6954= 2.3 mole% CO2 × w₃.

-3.610 = - 0.008w₁.

w₁ = 451.3 m³/min.

Thus, the flow rate = 0.123 × 451.3 = 55.51 kmol/min.

[b]. The average velocity = 150/ 18 seconds = 8.3 m/s.

[c]. Pipe Diameter can be calculated as follows;

0.123  × 8.3  × [3.12  × (pipe diameter)² / 4] = 55.51/60.

[1.0209  × 3.12]/4  × [pipe diameter]² = 0.9252.

0.8014065  ×  [pipe diameter]² = 0.9252.

[pipe diameter]² = 0.9252/ .8014065.

[pipe diameter]² = 1.15443.

[pipe diameter] = √1.15443.

[pipe diameter] = 1.2 m² = 1.0954m.

A) The gas flow rate (k.mol/min) upstream of the injection point is;

55.51 k.mol/min

B) The average velocity and the diameter of the pipe are respectively;

8.33 m/s and 1.072 m

Gas Flow rate in thermodynamics

Due to the fact that there is no reaction or accumulation in the pipeline, we can say that the input of CO₂ is equal to it's output. Thus;

Upstream + Injection = Downstream

A) If we assume that x is the flow rate of gas (kmol/min), then there is the we can write the balance as:

0.015x + (20/44) = 0.023(x + 20/44)

Expanding gives us;

0.015x + 0.4545 = 0.023x + 0.01045

Solving for x gives;

x = 55.51 kmol/min

B) Formula for velocity is;

v = distance/time

Thus, since the length of the pipe is 150 m/s and time is 18 seconds, then velocity is;

v = 150/18

v = 8.33 m/s

Now, volumetric flow rate is calculated from;

Q = q' * ρ

where;

q' is gas flow rate

ρ is gas density

Thus;

Q = 55.51 * 0.123

Q = 451.3 m³/min = 7.522 m³/s

We can also express average velocity as;

v = Q/A

where A is area = πD²/4

Thus;

8.33 = 7.522/(πD²/4)

Making D the subject of the formula gives;

D = √((4 * 7.522)/(8.33π))

D = 1.072 m

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what is functional group of ethers?​

Answers

Answer:

Explanation:The ether functional group consists of an oxygen atom that forms single bonds with two carbon atoms

Li atoms in 3.7 moles

Answers

Answer:

We know that there are 6.022 * 10²³ atoms in 1 mole of any element

So, that means that there are 6.022 * 10²³ atoms in 1 mole of Li (Lithium)

Atoms in 3.7 Moles:

atoms in one mole = 6.022 * 10²³

atoms in 3.7 moles = 6.022 * 10²³ * 3.7

atoms in 3.7 moles = 22.28 * 10²³

atoms in 3.7 moles = 2.228 * 10²⁴

pls help! I'll give u 10 points and the brainlest answer!!!​

Answers

Answer:

371km

Explanation:

the lower the more fuel there is

Sketch the titration curve for the titration of a generic weak base B with a strong acid. The titration reaction is
B+H+⇌BH+
On the curve indicate the points that correspond to the following:
a) the equivalence point.
b) the region with maximum buffering) the point where pH = pKbd) the region where pH depends only on [B]e) the region where pH depends only on [BH+]f) the region where pH depends only on the amount of excess strong acid

Answers

Answer:

Kindly check the attached picture.

Explanation:

Titration is one of the useful concept or practical in chemistry which is used in the determination of the concentration of a particular chemical specie. Without mincing words, let us dive straight into the solution to the question;

(a) Determining the equivalence point using the graph.

=> The equivalence point is the point at which there has been been "enough" addition of the acid to the base to give us the congugate acid. In the diagram showing the curve, it is the point labelled (a).

(b)The next thing is to determine the region with maximum buffering.

=> The position with the maximum buffering ranges from the point labelled (b) in the graph and it is the point when the acid and the base has been added. But the point with the maximum buffering is labeled as point (c).

(c). Determination of the point where pH = pKb.

=> The Point in which the pH = pKb is the point a

(d). The region where pH depends only on [B].

=> The starting point in the point in which the pH is dependent on the concentration of the base, [B].

(e). The region where pH depends only on [BH+].

=> This is the same point with point labelled as (a). Thus, point (a) and (e) are the same.

(f). The region where pH depends only on the amount of excess strong acid is the point labelled as (f) which is known as the post equivalence point.

If you worked at a job for $9.00/hour, what type of correlation is the number of hours worked and your take-home pay?

Answers

Answer:

There are no options to this question, however, it can be answered. The answer is:

POSITIVE CORRELATION

Explanation:

Correlation refers to the relationship between two variables. It shows how related two variables are to one another. Hence, when two variables are correlated, there exists a relationship between them. Correlation can either be positive or negative depending on how related they are.

A positive correlation is that correlation in which the two variables are influenced to go in the same direction. That is, when one variable increases, the other variable increases as well and vice versa. This is the case in this question regarding the correlation between number of hours worked and take-home pay.

As the number of hours worked increases, the take-home pay also increases and vice versa. Hence, it is a type of POSITIVE CORRELATION

H3C - CH2 - CEC - CH3
Compound name

Answers

Answer:

2-pentene

hope this helps :)

Explanation:

The pH of a solution of 19.5 g of malonic acid in 0.250 L is 1.47.The pH of a 0.300 M Solution of sodium hydrogen malonate is 4.26. What are the values of Ka1and Ka2

Answers

Answer:

[tex]Ka_1=1.61x10^{-3}[/tex]

[tex]Ka_2=1.01x10^{-8}[/tex]

Explanation:

Hello.

In this case, since the stepwise dissociation of malonic acid which is a diprotic acid that we are going to symbolize by H₂A, is:

[tex]H_2A\rightleftharpoons H^++HA^-;Ka_1\\\\HA^-\rightleftharpoons H^++A^-;Ka_2[/tex]

The first ionization has the following equilibrium expression:

[tex]Ka_1=\frac{[H^+][HA^-]}{[H_2A]}[/tex]

Whereas the concentration of H⁺ equals the concentration of HA⁻ and is computed via the pH:

[tex][H^+]=[HA^-]=10^{-pH}=10^{-1.47}=0.0339M[/tex]

Next, we compute the molarity of the 19.5 g of malonic acid (molar mass = 104.06 g/mol) as shown below:

[tex][H_2A]=\frac{19.5g/(104.06 g/mol)}{0.250L}=0.750M[/tex]

Thus, Ka1 turns out:

[tex]Ka_1=\frac{(0.0339)(0.0339)}{0.750-0.0339}=1.61x10^{-3}[/tex]

Now, for the second ionization, since the 0.300-M sodium hydrogen malonate is the source of HA⁻, and the pH is 4.26, we can compute the concentration of both H⁺ and A⁻² again by considering the pH:

[tex][H^+]=[A^-^2]=10^{-4.26}=5.50x10^{-5}M[/tex]

Therefore Ka2 turns out:

[tex]Ka_2=\frac{[H^+][A^{-2}]}{[HA^-]}=\frac{(5.50x10^{-5})(5.50x10^{-5})}{0.300-(5.50x10^{-5})}\\ \\Ka_2=1.01x10^{-8}[/tex]

Best regards!

If a sample of CO2 contains 48 g of oxygen, how many moles of CO2 are there?

Answers

Answer:

0.75 moles of CO2

Explanation:

molar mass of CO2⇒ 44.01 g/mol

molar mass Oxygen ⇒ 31.998 g/mol

divide the mass given by molar mass of oxygen  so

48÷31.998= 1.50009376 moles of O

then you use the ration of oxygen to carbon to find the moles of CO2 which is one mole of CO2 for 2 moles of oxygen

1.50009376 moles of O ×[tex]\frac{1}{2}[/tex] = 0.75004688

with sig figs

0.75 moles of CO2

How many F atoms are present in 3.16 moles of BaF2? show work

Answers

Answer:

3.80 × 10²⁴ atoms of F

Explanation:

Step 1: Given data

Moles of barium fluoride (BaF₂): 3.16 mol

Step 2: Calculate the moles of fluorine in 3.16 moles of barium fluoride

The molar ratio of BaF₂ to F is 1:2. The moles of F in 3.16 moles of BaF₂ are 2/1 × 3.16 mol = 6.32 mol.

Step 3: Calculate the atoms of F in 6.32 moles of F

We will use Avogadro's number: there are 6.02 × 10²³ atoms of F in 1 mole of atoms of F.

6.32 mol × (6.02 × 10²³ atom/1 mol) = 3.80 × 10²⁴ atom

Identify the change of state occurring in each situation. your friend's perfume producing an aroma that fills the room making ice cream from milk in an ice cream maker formation of frost on a cold windshield overnight wax dripping from a candle naphthalene solid (found in moth balls) producing fumes in the closet to deter moths your breath fogging up on your car windshield on a cold winter day

Answers

Answer:

The solution to this question can be defined as follows:

Explanation:

[tex]W_{ax}[/tex] Naphthalene falls off from candle something, strong fumes-sublimation produces. On a rainy day in winter, the breath fogging up on your cor's windshield. Brost formation on an overnight deposition on a frozen windshield. Making milk ice cream freezing the perfuming scent that fills the creation of the room.

10. Which of the following is NOT correctly matched?

A. Salt: Na and C: Element

B. Water: H and O: Corapound

C. Carbon dioxside: C and O: Compound

D. Magnesium chloride: Mg and C: Compound​

Answers

Answer:

A. because salt : Na and Cl, not C

using this chemical might discolour equipment and surfaces​

Answers

Answer: do not know how to answer this

Explanation:

6. Clownfish, sea anemone, coral, sea urchins, sponges and parrot fish are 5 points
just a few examples of the large variety of organisms that can be found in
a coral reef. The coral reef and its inhabitants (residents) are suffering due
to several factors such as pollution, coastal development, sedimentation
and destructive fishing practices. What would be the most likely result if
some of the species in the coral reef are destroyed? *

Answers

Answer:

The orange-and-white clownfish you know from Hollywood is only one of 30 species of clownfish that live in coral reefs around the world; small in size and big in personality, these tiny comedians have one of the most unique lifestyles in the reef. The orange-and-white clownfish you know from Hollywood is only one of 30 species of clownfish that live in coral reefs around the world; small in size and big in personality, these tiny comedians have one of the most unique lifestyles in the reef.

Explanation:

point being, it would be absolutely terrible

Coral reef are the biggest biodiversity in the world. Therefore, destruction of coral reefs definitely affect the aquatic livings. As well as it leads to erosion of seashore lines.

What are coral reefs?

Corals reefs are the habitat of 25% of sea organisms. It means there are well over a million species that rely on coral reefs for their existence. The reef offers these organisms the vital food, habitat, and breeding grounds required for the survival of their species.

The marine biodiversity would suffer greatly if their homes vanished. And many fish, turtles, and other species would vanish in a domino-like fashion.

Coral reefs are threatened by a number of things, such as local threats like overfishing, destructive fishing methods, coastal development, pollution, and careless tourism, as well as global effects of climate change like warming seas and rising CO₂ levels in the water. Natural phenomena like hurricanes, El Nio, and diseases are also a threat to oral reefs.

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the de broglie equation predicts that the wavelength (in m) of a proton moving at 1000 m/s is what?
(h=6.63 x 10^-34J•s; mass od a photon = 1.673 x 10^-24

Answers

Explanation:

from

de Broglie wavelength= h/ mv

substitute the values

joules= mass(kg) × acceleration (m/s^2) × distance(m)= kgm^2/s^2.

sorry I don't have my calc with me

According to De Broglie's Hypothesis, matter has both particle and wave properties. The wavelength of De Broglie is given as λ = h p,

wavelength (in m) of a proton =  11.09 x[tex]10^ {-55[/tex] m.

What is de Broglie statement?According to De Broglie's Hypothesis, matter has both particle and wave properties. The wavelength of De Broglie is given as λ = h p, where represents the particle momentum, and can be written as: λ= h m v.The de Broglie hypothesis demonstrated that wave-particle duality was a fundamental principle shared by both radiation and matter, rather than an aberrant behavior of light.De Broglie's equation does not apply to larger particles; rather, it only applies to microscopic particles such as electrons, protons, and neutrons. De Broglie's equation is only valid for moving microscopic particles.

λ= h m v.

= 6.63 x [tex]10^{-34}[/tex] x  1.673 x [tex]10^{-24[/tex]x 1000

= 11.09 x[tex]10^ {-55[/tex] m

To learn more about :  De Broglie's Hypothesis

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I need help pls... look at photo​

Answers

Answer:

LA PRIMERA ES N

Explanation:

2 nitrogen molecules are present
1 oxygen molecules
And 1 N20 molecules

A scientist plans to find out the cause of decrease in bird population in a location. He interviews 50 people who work in the local oil mine and 45 of them believe that the mine does not affect the birds. The scientist concludes that 90 percent of people in the location believe that the local oil mine does not cause decrease in bird population. Why is the scientist's conclusion most likely unreliable? (2 points)

Group of answer choices

a. the results of the investigation cannot be repeated

b. the source of information could be biased

c. bird population cannot be measured accurately

d. the investigation is done by only one person

Answers

Answer:

Explanation:

What is the reason behind an atom being neutral?

Answers

When an atom has an equal number of electrons and protons it has an equal number of negative charge (the electrons) and positive electric charges (the protons). The total electric charge of the atomic is therefore zero
^^^what they said, don’t worry, they phrased it better than I would but the users right

Which atom has exactly 15 protons?

Answers

Answer:

Phosphorus

Explanation:

A graduated cylinder is filled to an initial volume of 25mL. A solid object is dropped into the graduated cylinder. The final volume of the graduated cylinder is 60mL. The mass of the object is 140g. What is the density of the solid object?

Answers

Answer:

The answer is 4 g/mL

Explanation:

The density of a substance can be found by using the formula

[tex]density = \frac{mass}{volume} \\ [/tex]

volume = final volume of water - initial volume of water

volume = 60 - 25 = 35 mL

From the question we have

[tex]density = \frac{140}{35} \\ [/tex]

We have the final answer as

4 g/mL

Hope this helps you

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Read the sentence carefully and choose the option that answers the question.Los voluntarios de la comunidad tiran o reciclan la basura para m.Which pronoun would you use to replace the indirect object in the sentence above?Remember: The indirect object pronoun answers the question "to whom or for whom" in the sentence. Le Las Les Me 1 Mr. Baker calculated the area of 4 different styles of rugs. The areas of the 4 rugs are shown. OS MARULUGARES PARA P ALETICO ZORLUFERITY A = 50 m2 A5 m2 A = 2 m2 A = 15 m2 Whlch list shows the rugs in order from least area to greatest area? A Oval Rug, Square Rug, Circular Rug, Rectangular Rug B Oval Rug, Square Rug, Rectangular Rug, Circular Rug C Square Rug, Oval Rug, Rectangular Rug, Circular Rug D Circular Rug, Rectangular Rug, Square Rug, Oval Rug How is the executive branch structured and what are its powers? Create a summary of no less than 125 words of a show that would NOT go over well with television producers because it is targeted to people in the least desirable groups. Include the title of the show, the main characters, and a description of the show's premise. Explain why this show would NOT go over well with television producers. By considering the discriminant, find thevalue of the constant p such that thefollowing equation has equal/repeatedsolutions.4x2 + 8x + p = 0 Test anxiety appears only before an exam.Please select the best answer from the choices providedTF Why id evaporation considered to be an endothermic process?A) Heat is being released to change the substance from a liquid to a gasB) Heat is being absorbed to change the substance from a liquid to a gasC) Heat is being released to change the substance from a gas to a liquid what is meant by hydrogen bond what's the value of X? A groundskeeper needs grass seed to cover a circular field. 150 feet in diameter. A store sells 50-pound bags of grass seed. One pound of grassseed covers about 60 square feet of field. What is the smallest number of bags the groundskeeper must buy to cover the circular field? In American cities, __________ played the largest role in allowing many residents to have the freedom to live farther away from their jobs.A.flight networksB.automobilesC.central business districtsD.streetcars (5x10^3) + (4.3x10^4)= A construction worker estimates that a kitchen will take 1 Person 200 hours. If 5 people work on the job for 8 hours a day, how many days will it take for them to complete the job? A) 4B) 5C) 6D) 7 Choose the best statement of the octet rule from those listed below atoms lose 8 electrons to become valent atoms lose 8 electrons to become valent, atoms want 8 valence electrons atoms want 8 valence electrons atoms tend to react until they have 8 valence electrons atoms tend to react until they have 8 valence electrons, atoms tend to react in order to have the s2p4 configuration atoms tend to react in order to have the s2p4 configuration, atoms tend to react in order to gain 8 valence electrons atoms tend to react in order to gain 8 valence electrons As Mexican troops drew closer to the Alamo, the Texans ________________.a.retreated to smaller quarters within the mission chapelb.sent word to Gonzales for reinforcementsc.sent word to the United States requesting statehoodd.suffered a rebellion from within the fort can yall please answer this A common health myth is that people should drink at least eight glasses of water per day. While staying hydrated is important, why could this advice be inaccurate for different people? (Site 1) What is the slope of the line y = -2? What is the difference between explicit and implicit ideas? (5 points)Select one:a.Implicit ideas must be inferred, and explicit ideas are stated directly.b.Explicit ideas must be inferred, and implicit ideas are stated directly.c.Both implicit and explicit ideas help readers draw conclusions, but only implicit ideas are facts.d.Explicit ideas always appear in texts; implicit ideas sometimes appear in texts. Just the last question thank you!!