So what i did was first used magnify= - d image / d original
m= -2/1= di/32. <--- I solved for di which was = -64. Then i plugged it in to this equation...
(1/di)+(1/do)=(1/focus). So i got (1/32)+(1/-64)=(1/f) :: Focus= 64.
I plugged that number in it was wrong, so i thought maybe they wanted the radius that was double the focus, so i put 128, and it was also wrong. BTW everything is in cm, and they want the answer in cm, so i didn't conver to meters.