Q: A solid if formed by adjoining two hemispheres to the ends of a right circular cylinder. The total volume of the solid is 12 cm^3. Find the radius of the cylinder that produces the minimum surface area. OK, I got about halfway through my problem before I got lost. V of shpere= 4/3(pi)r^3 V of cylinder= (pi)r^2(h) total V= 2(4/3*pi*r^30) + (pi*r^2*h) 12=pi*r^2(2*4/3*r+h) which turns into 12/pi*r^2=8/3*r+h so h=(12/pi*r^2) - (8/3*r) Now I'm lost.