Answer:
D
Step-by-step explanation:
hope this helps
Answer:

Step-by-step explanation:
The exponential decrease formula that we must use is:

Where A is the amount of thorium as a function of time
is the initial amount and k is the decrease rate
We know that initially there are 50 gr and that you decay 50% every 1.9 years.
So


We solve the equation for k





After 22.8 years the amount of thorium that exists is:


Your answer would be A) a+c+e
a-b+c
b-c+d
c-d+e
+
——————
a+c+e
Answer:
Write the formula for one measurement, then solve the formula for the different measurement you want to find and use this new formula to find that measurement.
Step-by-step explanation:
We can understand this through an example.
If we need to find the lenght of a rectangle whose width is 4 feet and whose perimeter is 28 feet, we can use a formula for one measurement to write a formula for a different measurement:
- We need to write the formula for the perimeter of a rectangle:

Where "l" is the lenght and "w" is the width.
- Since we know the width and the perimeter of the rectangle and we need to find the lenght, we can solve for "l":

Now we get a new formula for calculate a differente measurement (the lenght of the rectangle).
- Substituting values, we get:
