A radioactive substance decays exponentially: The mass at time t is m(t) = m(0)e^kt, where m(0) is the initial mass and k is a negative constant. The mean life M of an atom in the substance is
[infinity]
M = âk â« te^kt dt.
0

For the radioactive carbon isotope, 14C, used in radiocarbon dating, the value of k is -0.000121. Find the mean life of a 14C atom.

Answer:

208

Step-by-step explanation:

use the formula x-98=110 since range is the highest number of the group subtracted by the lowest.

[tex]\implies {\blue {\boxed {\boxed {\purple {\sf { A. \:2 \sqrt{30} }}}}}}[/tex]

[tex]\sf \bf {\boxed {\mathbb {STEP-BY-STEP\:EXPLANATION:}}}[/tex]

[tex] = \sqrt{3} \times \sqrt{8} \times \sqrt{5} [/tex]

[tex] = \sqrt{3 \times 2 \times 2 \times 2 \times 5} [/tex]

[tex] = \sqrt{ ({2})^{2} \times 2 \times 3 \times 5} [/tex]

[tex] = 2 \sqrt{2 \times 3\times 5} [/tex]

[tex] = 2 \sqrt{30} [/tex]

[tex] \sqrt{ ({a})^{2} } = a[/tex]

[tex]\bold{ \green{ \star{ \orange{Mystique35}}}}⋆[/tex]

Answer:

A. 2√30

Step-by-step explanation:

[tex] \small \sf \: \sqrt{3} \times \sqrt{8} \times \sqrt{5} \\ [/tex]

split √8

[tex] \small \sf \leadsto \sqrt{3 × 2 × 2 × 2 × 5} [/tex]

[tex] \small \sf \leadsto \: 2 \sqrt{2 \times 3 \times 5} [/tex]

[tex] \small \sf \leadsto \: 2 \sqrt{30} [/tex]

Answer:

Place value of 1 = 1 × 10 = 10

Step-by-step explanation:

In 382619,

Place of 1 = Tens

Place value of 1 = 1 × 10 = 10

Step-by-step explanation:

The ratio is 2 to 5 or 2:5 or 2/5. All these describe the ratio in different forms of fractions. The ratio can consequently be expressed as fractions or as a decimal.

A ratio of 2 : 5 states a comparison between two quantities.

A ratio is a comparison between two similar quantities in simplest form.

Proportions are of two types one is the direct proportion in which if one quantity is increased by a constant k the other quantity will also be increased by the same constant k and vice versa.

In the case of inverse proportion if one quantity is increased by a constant k the quantity will decrease by the same constant k and vice versa.

Given, a ratio 2 : 5.

Suppose it is a ratio of no. of pens to no. of pencils.

So, a ratio 2 : 5 states for every 2 pens there are 5 pencils out of 7 pen and pencils.

We can also write no. of pens = 2/(2+ 5) = 2/7 and for pencils it is 5(2+5)

= 5/7.

Generally, ratios are in simplest form we can have more pens and pencils here but it must be in the multiple of 7.

learn more about ratios here :

https://brainly.com/question/13419413

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Answer:

A 1/2

Step-by-step explanation:

Ratio of short length to hypotenuse

= cos60

= 1/2

Step-by-step explanation:

i would love to say 2 but the word had shows that he does not have 3 apples anymore so the answer is either

0 or -1

The number of apples left after taking the 1 apple from 3 apples by a person is 2 apples.

Subtraction stands for the resultant number, which exists acquired by taking the difference of a number from another number.

Let a number be subtracted from the number b. Then the consequent number after subtracting b from a will be,

d = b - a

Here, (a, b) exists the real numbers.

It exists given that there exist 3 apples. 1 apple stand was taken. Let's assume after taking the 3 apples, that there exist x apples remaining.

As there exist a total of 3 apples and 1 apple stand taken, then to estimate the number of apples left, we must subtract 1 apple from 3 apples.

Therefore, the total apples left exist,

x = 3 - 1

x = 2

To learn more about subtraction operation

https://brainly.com/question/26883387

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Answer:

The quadrilateral is a rhombus

Step-by-step explanation:

Given

[tex]A = (2, 8)[/tex]

[tex]B = (3, 11)[/tex]

[tex]C = (4, 8)[/tex]

[tex]D=(3, 5)[/tex]

Required

The true statement

Calculate slope (m) using

[tex]m = \frac{y_2 - y_1}{x_2 - x_1}[/tex]

Calculate distance using:

[tex]d= \sqrt{(x_2 - x_1)^2 + (y_2 -y_1)^2}[/tex]

Calculate slope and distance AB

[tex]m_{AB} = \frac{11 - 8}{3 - 2}[/tex]

[tex]m_{AB} = \frac{3}{1}[/tex]

[tex]m_{AB} = 3[/tex] -- slope

[tex]d_{AB}= \sqrt{(3 - 2)^2 + (11 -8)^2}[/tex]

[tex]d_{AB}= \sqrt{10}[/tex] -- distance

Calculate slope and distance BC

[tex]m_{BC} = \frac{8 - 11}{4 - 3}[/tex]

[tex]m_{BC} = \frac{- 3}{1}[/tex]

[tex]m_{BC} = -3[/tex] -- slope

[tex]d_{BC} = \sqrt{(4-3)^2+(8-11)^2[/tex]

[tex]d_{BC} = \sqrt{10}[/tex] --- distance

Calculate slope CD

[tex]m_{CD} = \frac{5 - 8}{3 - 4}[/tex]

[tex]m_{CD} = \frac{- 3}{- 1}[/tex]

[tex]m_{CD} = 3[/tex] -- slope

[tex]d_{CD} = \sqrt{(3-4)^2+(5-8)^2}[/tex]

[tex]d_{CD} = \sqrt{10}[/tex] -- distance

Calculate slope DA

[tex]m_{DA} = \frac{8 - 5}{2 - 3}[/tex]

[tex]m_{DA} = \frac{3}{- 1}[/tex]

[tex]m_{DA} = -3[/tex] -- slope

[tex]d_{DA} = \sqrt{(2-3)^2 + (8-5)^2}[/tex]

[tex]d_{DA} = \sqrt{10}[/tex]

From the computations above, we can see that all 4 sides are equal, i.e. [tex]\sqrt{10}[/tex]

And the slope of adjacent sides are negative reciprocal, i.e.

[tex]m_{AB} = 3[/tex]  and [tex]m_{CD} = -3[/tex]

[tex]m_{CD} = 3[/tex] and [tex]m_{DA} = -3[/tex]

The quadrilateral is a rhombus

9514 1404 393

Answer:

  x = 19

  A = 30°

  B = C = 75°

Step-by-step explanation:

In an isosceles triangle, the angles opposite the congruent sides have the same measures.

  A = B

  3x +18 = 7x -58

  76 = 4x . . . . . . . . add 58-4x

  19 = x . . . . . . . . . divide by 4

Then the equal angles measure ...

  A = B = 3(19) +18 = 75

  C = 2(19) -8 = 30

Angles A, B, C measure 75°, 75°, 30°, respectively.

_____

Alternate solution

The sum of angles in a triangle is 180°, so you could write ...

  (3x +18) +(7x -58) +(2x -8) = 180

  12x = 228 . . . . . add 48

  x = 19 . . . . . divide by 12

Answer:

B. -21.012÷ -3.4

its yr correct ans.

hope it helps

Answer:

2/3

Step-by-step explanation:

[tex]2 \frac{1}{4} : \frac{1}{2}[/tex] = [tex]\frac{9}{4} : \frac{1}{2}[/tex]

[tex]\frac{\frac{9}{4} }{\frac{1}{2} }[/tex] = [tex]\frac{3}{x}[/tex]

3 * 1/2 = 9/4x

3/2 = 9/4 x

x = 3/2 ÷ 9/4 = 3/2 * 4/9 = 12/18 = 6/9 = 2/3

Answer:

The call more is cheaper than talk-now.

Step-by-step explanation:

The companies charge a flat fee plus an added cost for each minute or part of a minute used for two companies are as follows :

Call-More: C = 0.40t + 25 Talk-Now: C = 0.15t + 40

We need to find which company is cheaper if a customer talks for 50 minutes.

For call more,

C = 0.40(50) + 25 = 45 units

For talk-now,

C = 0.15(50) + 40 = 47.5 units

So, it can be seen that call more is cheaper than talk-now.

Answer:

1

Step-by-step explanation:

tan(1)tan(2)....tan(89)=?

Recall tan(90-x)=cot(x) and cot(x)tan(x)=1.

tan(89)=tan(90-1)=cot(1)

tan(88)=tan(90-2)=cot(2)

tan(87)=tan(90-3)=cot(3)

...

tan(46)=tan(90-44)=cot(44)

tan(45)=tan(90-45)=cot(45)

So we can replace the last half of the factors with cotangent of the angles in the first half.

The only one that doesn't get a partner is the exact middle factor which is tan(45).

So this is whar we have:

tan(1)tan(2)tan(3)....tan(45)....cot(3)cot(2)cot(1)

So you should see that cot(1)tan(1)=1 and cot(2)tan(2)=1 and so on....

So the product equals tan(45) and tan(45)=1 using unit circle.

[tex] \large{ \tt{❁ \: USING \: INTERNAL \: SECTION \: FORMULA: }}[/tex]

[tex] \large{ \bf{✾ \: P(x \:, y \: ) = ( \frac{m_{1}x_{2} + m_{2}x_{1}}{m_{1} + m_{2}} \: ,\: \frac{m_{1}y_{2} + m_{2}y_{1}}{m_{1} + m_{2}}) }}[/tex]

[tex] \large{ \bf{⟹ \: ( \frac{8m + 3n}{m + n} , \: \frac{9m -n}{m + n}) }}[/tex]

[tex] \large{ \bf{ ⟼\frac{8m + 3n}{m + n} - \frac{9m - n}{m + n} - 2 = 0 }}[/tex]

[tex] \large{ \bf{⟼ \: \frac{8m + 3n - 9m + n}{m + n} - 2 = 0 }}[/tex]

[tex] \large{ \bf{⟼ \: \frac{4n - m}{ m + n} - 2 = 0 }}[/tex]

[tex] \large{⟼ \: \bf{ \frac{4n - m}{m + n }} = 2} [/tex]

[tex] \large{ \bf{⟼ \: 4n - m = 2m + 2n}}[/tex]

[tex] \large{ \bf{⟼ \: 4n -2 n = 2m + m}}[/tex]

[tex] \large{ \bf{⟼2n = 3m}}[/tex]

[tex] \large{ \bf{⟼ \: 3m = 2n}}[/tex]

[tex] \large{ \bf{⟼ \: \frac{m}{n} = \frac{2}{3} }}[/tex]

[tex] \boxed{ \large{ \bf{⟼ \: m : \: n = 2: \: }3}}[/tex]

-Hope I helped! Let me know if you have any questions regarding my answer and also notify me , if you need any other help! :)

▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁

[tex] {64}^{ \frac{2}{3} } \div {27}^{ \frac{5}{3} } \times 54 \\ = > \: {({2}^{3} )}^{ \frac{2}{3} } \div ({{3}^{3}})^{ \frac{5}{3} } \times 54 \\ = > \: {2}^{2} \div {3}^{5} \times 54 \\ = > \: 4 \div 243 \times 54 \\ = > \: 4 \div 13122 \\ = > \: \frac{4}{13122} \\ = > \: \frac{2}{6561} [/tex]

Hope it helps!!!!!!!!!!

Answer:

3/10

Step-by-step explanation:

Total possibilities = 10

favourable possibilities = 3

Answer:

A

Step-by-step explanation:

There is a 1 out of 10 chance that it will land on 2.

There is a 1 out of 10 chance that it will land on 4.

There is a 1 out of 10 chance that it will land on 7.

[tex]\frac{1}{10}\cdot3=\frac{3}{10}[/tex] so the anwser is A.

Answer:

the adjustment made to the cost of goods sold is -$2,014

Step-by-step explanation:

The computation of the adjustment made to the cost of goods sold is given below:

Total actual overhead expenses $110,822

Less: Total overheads allocated -$112,836

Adjustment made to the cost of goods sold -$2,014

Hence, the adjustment made to the cost of goods sold is -$2,014

The same should be considered

Answer:

The answer is "0.9102"

Step-by-step explanation:

P(student spell correct) = 0.6

P(student spell incorrect)=1-0.6=0.4

X=the pupil will be allowed to sit down after receiving three slaps on the hand Thus, X would assume Value

X=0 (student sit sans getting whacks)

X=1 (student sit down without receiving 1 whack) (student sit down without receiving 1 whack)

X=2 (student take a seat before receiving 2 whacks)

X=3 (student sit down after receiving 3 punches)

[tex]\to P(X)=0.6 \times 0.4^0 +0.6 \times 0.4 + 0.6 \times 0.4 ^2 + 0.6 \times 0.3^3[/tex]

             [tex]=0.6 \times 1+0.24 + 0.6 \times 0.09 + 0.6 \times 0.027\\\\=0.6 +0.24 + 0.054 + 0.0162\\\\=0.9102\\\\[/tex]

9514 1404 393

Answer:

Step-by-step explanation:

Rewriting the equations to make x the subject, we have ...

  x = y² -1 . . . . . [eq1]

  x = 1 - y . . . . . .[eq2]

At the points of intersection, the difference will be zero.

  y² -1 -(1 -y) = 0

  y² +y -2 = 0

  (y -1)(y +2) = 0

The y-coordinates of points A and B are 1 and -2.

The corresponding x-coordinates are ...

  x = 1 -{1, -2} = {1 -1, 1+2} = {0, 3}

Then A = (0, 1) and B = (3, -2).

__

A differential of area can be written ...

  (x2 -x1)dy = ((1 -y) -(y² -1))dy = (2 -y -y²)dy

Integrating this over the interval y = [-2, 1] gives the area.

  [tex]\displaystyle A=\int_{-2}^1(2-y-y^2)\,dy=\left.(2y-\dfrac{1}{2}y^2-\dfrac{1}{3}y^3)\right|_{-2}^1\\\\=\left(2-\dfrac{1}{2}-\dfrac{1}{3}\right)-\left(2(-2)-\dfrac{(-2)^2}{2}-\dfrac{(-2)^3}{3}\right)=\dfrac{7}{6}+4+2-\dfrac{8}{3}\\\\=\boxed{4.5}[/tex]

The area of the shaded region is 4.5 square units.

9514 1404 393

Answer:

  f = 2T/(v1 +v2)

Step-by-step explanation:

Multiply by the inverse of the coefficient of f.

  [tex]T=f\cdot\dfrac{v_1+v_2}{2}\\\\f=\dfrac{2T}{v_1+v_2}[/tex]

Answer:

0.5217

Step-by-step explanation:

P(more than 5 customer arrive):

P(X>=6)=1-P(X<=5)=  1-∑x=0x e-λ*λx/x!= 0.5217

Answer:

Click the rotate 'button' twice.

Observe.

The rotate button is rotating the image about the orgin.

Answer:

Click the rotate 'button' twice.

Observe.

The rotate button is rotating the image about the orgin.

Step-by-step explanation:

Answer:

y = [ 4 ]

Step-by-step explanation:

5y - 10 = 10

     +10  +10

5y = 20

/5     /5

y = 4

hope this helps ! ^^

Answer:

[tex]5y-10=10[/tex]

[tex]Add ~10[/tex]

[tex]5y=10+10[/tex]

[tex]5y=20[/tex]

[tex]divide ~by ~5[/tex]

[tex]y=4[/tex]

[tex]ANSWER: y=4[/tex]

-----------------------------

HOPE IT HELPS

HAVE A GREAT DAY!!

Answer:

The rate at which the distance between the cars increasing two hours later=52mi/h

Step-by-step explanation:

Let

Speed of one car, x'=48 mi/h

Speed of other car, y'=20 mi/h

We have to find the rate at which the distance between the cars increasing two hours later.

After 2 hours,

Distance traveled by one car

[tex]x=48\times 2=96 mi[/tex]

Using the formula

[tex]Distance=Time\times speed[/tex]

Distance traveled by other car

[tex]y=20\times 2=40 mi[/tex]

Let z be the distance between two cars after 2 hours later

[tex]z=\sqrt{x^2+y^2}[/tex]

Substitute the values

[tex]z=\sqrt{(96)^2+(40)^2}[/tex]

z=104 mi

Now,

[tex]z^2=x^2+y^2[/tex]

Differentiate w.r.t t

[tex]2z\frac{dz}{dt}=2x\frac{dx}{dt}+2y\frac{dy}{dt}[/tex]

[tex]z\frac{dz}{dt}=x\frac{dx}{dt}+y\frac{dy}{dt}[/tex]

Substitute the values

[tex]104\frac{dz}{dt}=96\times 48+40\times 20[/tex]

[tex]\frac{dz}{dt}=\frac{96\times 48+40\times 20}{104}[/tex]

[tex]\frac{dz}{dt}=52mi/h[/tex]

Hence, the rate at which the distance between the cars increasing two hours later=52mi/h

Answer:

I think it is 160 x2 so you would probably divide 160 by x2 which would 144

Step-by-step explanation:

Answer:

The correct one is 3 over b equals 7 over a

Answer:

3/b = 7/a

Step-by-step explanation:

I took it on Edge

Answer:

59 / 71

Step-by-step explanation:

Given the data :

A B C Total

Male 20 10 13 43

Female 15 2 11 28

Total 35 12 24 71

The probability of randomly selecting a Student that got B ;

Probability = required outcome / Total possible outcomes

P(getting B) = number of students who got B / total number of students

P(getting B) = 12 / 71

Probability of getting B = 12 /71

Probability of not getting B = P(getting B)' = 1 - P(getting B)

Probability that student did not get "B" = 1 - 12/71 = 59 / 71

Answer:

$ 1943

Step-by-step explanation:

You two congruent trapezoids.

Find the area of one and multiply by 2.

A = [tex]\frac{base_{1} + base_{2} }{2}[/tex] x  h

  = [tex]\frac{28+39}{2}[/tex] x 14.5

  = [tex]\frac{67}{2}[/tex] x 14.5

  = 33.5 x 14.5

  = 485.75

  = 485.75 x 2 (Two trapezoids)

  = 971.50

  = 971.50 x 2 (two dollars a square foot)

  = 1943.00

Answer:

the answer is 35/64(in fraction) but in decimals it's 0.55