1. The problem statement, all variables and given/known data 1) The medium-power objective lens in a laboratory microscope has a focal length fobjective = 3.70mm . If this lens produces a lateral magnification of -42.5, what is its "working distance"; that is, what is the distance from the object to the objective lens? 2) What is the focal length of an eyepiece lens that will provide an overall magnification of -130? Assume student's near-point distance is N = 25 cm 2. Relevant equations m=-di/fobjective 3. The attempt at a solution I tried using that formula to solve for this distance for object but it doesn't work out. I got that formula from a book where they assume that do is approx to be fobjective. Tbh, I don't quite understand how to get this "working distance". Anyone can help?