Answer:
or 
Step-by-step explanation:
step 1
Find the volume of the rectangular prism
we know that
The volume of a rectangular prism is

In this problem we have



substitute in the formula

step 2
Find the difference between the volume of the prism and the volume of the storage container


Recall the logarithm rules :
a^y = x is the same as log_a x = y
In this case,
a = 18
y = r - 10
x = 93
So,
18^ (r-10) = 93
is the same as
log_18 93 = r - 10
Solve for r to get :
10 + log_18 93 = r
The answer would be B. find a relationship between what is given and what must be found.