In 2014 there were approximately 31,800 firearm fatalities. express this quantity in deaths per hour.

Well there are 8,760 hours in 1 year.  So divide 31800 by 8760 and get 3.63 per hour.  (not sure how many decimal places you need)

To solve this we are going to use the exponential function: 
where
is the final amount after years
is the initial amount
is the decay  or grow rate rate in decimal form
is the time in years

Expression A 

Since the base (0.95) is less than one, we have a decay rate here.
Now to find the rate , we are going to use the formula: *100%
*100%
*100%
5%
We can conclude that expression A decays at a rate of 5% every three months.

Now, to find the initial value of the function, we are going to evaluate the function at 





We can conclude that the initial value of expression A is 624.

Expression B

Since the base (1.12) is greater than 1, we have a growth rate here.
To find the rate, we are going to use the same equation as before:
*100%
*100
*100%
*100%
12%
We can conclude that expression B grows at a rate of 12% every 4 months.

Just like before, to find the initial value of the expression, we are going to evaluate it at 





The initial value of expression B is 725.

We can conclude that you should select the statements:
- Expression A decays at a rate of 5% every three months, while expression B grows at a rate of 12% every fourth months. 

- Expression A has an initial value of 624, while expression B has an initial value of 725.