A concave mirror has focal length f.

(a) If you look into the mirror from a distance less than f, is the image you see upright or inverted? 

(b) If you stand at a distance greater than 2f, is the image upright or inverted? 

(c) If you stand at a distance between f and 2f, an image is formed but you cannot see it. Why not? Sketch a ray diagram and compare the locations of the object and image.