A certain digital camera having a lens with focal length 7.5 cm focuses on an object 1.85 m tall that is 4.25 m from the lens. (a) How far must the lens be from the photocells? (b) How tall is the image on the photocells? Is it erect or inverted? (c) A SLR digital camera often has pixels measuring 8.0 um by 8.0 um. How many such pixels does the height of this image cover?

I have part a and b, but I can't figure out c! help please!