(12) What would happen if there were two pinholes in the replacement panel?
Two pinholes would allow light to enter the camera at two places. Since both of the holes are small, light would travel in all directions from both holes. As a result, two images would form, showing the perspectives of the two holes.
(13) What would happen if the hole were the size of a baseball (assuming that the light could be limited to a single direction of entry)?
A hole the size of a baseball is not on the order of a wavelength of light. Light would continue to travel in its direction of entry, creating a circular picture on the paper. (In the actual situation of a simple pinhole camera formed from one container, the direction of light entry cannot be limited, so a hole the size of a baseball allows light from all directions to enter and the entire piece of photographic paper is overexposed.)
