Question

A fruit fly of height H sits in front of lens 1 on the central axis through the lens.The lens forms an image of the fly at a distance d = 30 cm from the fly; the image has the fly's orientation and height HI = 2.5 H. What are (a) the focal length f1 of the lens and (b) the object distance p1 of the fly? The fly then leaves lens 1 and sits in front of lens 2, which also forms an image at d = 30 cm that has the same orientation as the fly, but now HI = 0.86 H. What are (c) f2 and (d) p2?