There are 52 weeks in a year, so subtract 27 from 52.
52-27=25
There were 25 weeks with no rainy days
        
             
        
        
        
Let  . Then
. Then


and substituting these into the ODE gives



Let  , so that
, so that  . Then the ODE is linear in
. Then the ODE is linear in  , with
, with

Multiply both sides by  , so that the left side can be condensed as the derivative of a product:
, so that the left side can be condensed as the derivative of a product:

Integrating both sides and solving for  gives
 gives

Integrate again to solve for  :
:

and finally, solve for  by multiplying both sides by
 by multiplying both sides by  :
:

 already accounts for the
 already accounts for the  term in this solution, so the other independent solution is
 term in this solution, so the other independent solution is  .
.
 
        
             
        
        
        
First fine the volume of ur big box:
10x10x15
=1500
Then ur small one:
4x4x2
=32
Lastly, subtract the small one from the big one
1500-32
=1468
Ur answer is 1468in^3