The graph models the decay of a sample of iodine-125, where x is the time that has passed and y is the amount remaining in the sample in grams.

what was the size of the sample at the beginning of the experiment?

a. 12.5grams
b. 25grams
c. 50grams
d. 120grams

option C. 50 grams

Step-by-step explanation:

we know that

The size of the sample at the beginning of the experiment is equal to the y-intercept or initial value of the function

Remember that the y-intercept is the value of y when the value of x is equal to zero

In the context of the problem, the y-intercept is the size of the sample at the beginning of the experiment (x=0)

Looking at the graph

For x=0, y=50

therefore

The size of the sample at the beginning of the experiment was 50 grams