Hello!
The answer is:
A. There will be required 61 tons for the floor.
Why?
To solve the problem, we need to remember how to convert from tons to pounds, and inches to feet.


We are given the density of the whased gravel that is equal to:

Then, we need to calcualte the volume of the garage in order to know how much gravel will be required for the floor.
First, we need to convert the deep in inches to feet, so:

Now, calculating the volume of the garage, we have:

Where, for this case:

So,

Then, calculating how much gravel will be required for the floor, we have:

Hence, The answer is A. There will be required 61 tons for the floor.
Have a nice day!