Answer:
Step-by-step explanation:
The student needs to check all algebraic and mathmatical calculations for errors and typos.  I'm old and have been prone to making mistakes.
Cylinder A DIAMETER 12 ft and Height 13 ft
Cylinder B DIAMETER 10 ft and Height 16 ft
After pumping How much water remains in cylinder A
Volume of a cylinder  =  π(radius)²h is the normal form since they provided the diameter I will use     Volume of a cylinder  =  π(diameter/2)²h
Water remaining in A = Volume of A  - Volume of B   =  
VolA  - VolB  =  π(D for A/2)²H of A  -   π(D for B/2)²H of B
              writing if a little more condensed
VolA  - VolB  =  π(D for A/2)²H of A  -   π(D for B/2)²H of B
     Va - Vb    =   π(Da/2)²Ha  -   π(Db/2)²Hb
                      =  π [(Da²/2²)Ha - (Db²/2²)Hb]      factored out the π
                      =  π/4 [ Da²Ha  - Db²Hb]              factored out the (1/2)²
              I can't think of any other algebraic steps
Va - Vb = Water Remaining in Container A  =  π/4 [ Da²Ha  - Db²Hb]            
             =  π/4 [ (12²)(13)  - (10²)(16)]
             =  π/4 [ (144)(13)  - (100)(16)]
             =  π/4 [ 1872 - 1600 ]
             =  π/4 [272]
             =  π [ 272/4 ]   
             =  π [ 136 / 2]
             =  π [ 68 ]
             =  π (68)
             =  213.6  ft³             rounded to the nearest tenth
I checking my answer by using  V = πr²h         r = d/2
            Va - Vb = π [ra²ha - rb²hb]
                          = π [6²(13)  - 5²(16)]
                          = π [(36)(13) - (25)(16)]
                          = π [ 468 - 400]
                          = 68 π
                          = 213.6 ft³         I got the same answer
        
             =  π 
test