Well, first off, you see how all the answers say a fraction, then pi? that means that you don't calculate pi into your answer.
But lets see. The radius is 4. V=(4/3)pi*r^2
V=(4/3)pi*4^2
V=(4/3)pi*16
V=(4/3)*16*pi
V=(4/3)*(16/1)*pi
V=(4*16)/(3*1)*pi
V=64/3*pi
so the answer is (B) 64/3pi units cubed.
        
             
        
        
        
I'm pretty sure yes because a translation is just moving something in another direction and not rotating
        
             
        
        
        
The coordinates for D are (-4, -7)
First we must locate point B as it is vital to finding the midpoint of BD. To do this, we take the average of the endpoints AC since B is its midpoint. 
x values = -9 + 1 = -8
Then divide by 2 for the average -8/2 = -4
y values = -4 + 6 = 2
Then divide by 2 for the average 2/2 = 1
Therefore B must be (-4, 1)
Now we know the values of E must be the average of B and D. So we can write equations for each coordinate since we know they are averages. 
x - values = (Bx + Dx)/2 = Ex
(-4 + Dx)/2 = -4 ---> multiply both sides by 2
-4 + Dx = -8 ---> add -4 to both sides
Dx = -4
y - values = (By + Dy)/2 = Ey
(1 + Dy)/2 = -3 ---> multiply both sides by 2
1 + Dy = -6 ---> subtract 1 from both side
Dy = -7
So the coordinates for D must be (-4, -7)