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1 year ago

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The decay of 192 mg of an isotope is given by A(t)= 192e-0.015t, where t is time in years. Find the amount left after 55 years.

Round your answer to the nearest whole number.
A 83

B 84

C 42

D 189

1 answer:

statuscvo [17]1 year ago

6 0

Answer:

This is a typical radioactive decay problem which uses the general form:

A = A0e^(-kt)

So, in the given equation, A0 = 192 and k = 0.015. We are to find the amount of substance left after t = 55 years. That would be represented by A. The solution is as follows:

A = 192e^(-0.015*55)

A = 84 mg

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Answer:

The equations are:

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Step-by-step explanation:

Given

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Required

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In the first statement, we have that:

$T = 2Y$

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Solving further:

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1 year ago

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Now , these distance are equal :

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1 year ago

Suppose two different methods are available for eye surgery. The probability that the eye has not recovered in a month is 0.002

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Answer:

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Step-by-step explanation:

Let's define the following events:

A: method A is used

B: method B is used

NR: the eye has not recovered in a month

R: the eye is recovered in a month

The probability that the eye has not recovered in a month is 0.002 if method A is used, i.e., P(NR|A) = 0.002, so P(R|A) = 0.998.

When method B is used, the probability that the eye has not recovered in a month is 0.005, i.e., P(NR|B) = 0.005, so P(R|B) = 0.995.

40% of eye surgeries are done with method A, i.e., P(A) = 0.4

60% of eye surgeries are done with method B, i.e., P(B) = 0.6

If an eye is recovered in a month after surgery is done in the hospital, what is the probability that method A was performed? We are looking for P(A|R), then, by Bayes' Formula

P(A|R) = P(R|A)P(A)/(P(R|A)P(A) + P(R|B)P(B)) = 0.998*0.4/(0.998*0.4 + 0.995*0.6) = 0.4007

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2 years ago

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SashulF [63]

Answer:

Reflect the parent function over the x-axis, and translate it 8 units to the left.

Step-by-step explanation:

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Since there is a negative multiply the transformed function, there is a reflection in the x-axis.

Since 8 is adding, within the square root, there is a horizontal translation of 8 units to the left.

Therefore to graph the given function, reflect the parent function over the x-axis, and translate it 8 units to the left.

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1 year ago

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boyakko [2]

Answer:

c. $\frac{1}{5}$

Step-by-step explanation:

Given,

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OPTION C is correct.

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1 year ago