Answer: 
Step-by-step explanation:
We know that the general form of the exponential decay formula is
, where y is final amount remaining after t time, A is the original amount and r is the rate of decay
Now, the ratio of strontium-90 remaining, p , as a function of years, t , since the nuclear accident. 
Hence, the ratio of remaining since the nuclear accident is 
Answer:
c≈15.07
Step-by-step explanation:
c=a2+b2=11.12+10.22≈15.07481
It is B. You divide 10 by 25 and multiply it by 100
Answer:
B. 2x - 3
Step-by-step explanation:



Answer:
From -2<x<-1, the function F(X) is increasing. (B)
Really, it increases all from around -2.5<x<0.5
C is also the second answer, as it increases til around 2.5
It is decreasing from -4<x<-3. But increases right after. It then starts to slow down around x = 1 and go down again.
Which means (B) is your answer.
If you want to get fancy, its a polynomial and if you take the derivative for instantaneous rate, you will see f prime is increasing if you make an example function.