[填空题]
Two converging lenses, h r (b9ome5hp5g2ru .5n kscc7s mt-foc)4a)sone with $f=4.0\mathrm{~cm}$ and the other with $f=44\mathrm{~cm}$ are made into a telescope.
(a) What are the length and magnification? Which lens should be the eyepiece?
The distance between the two lenses is cm
M = $\times $
f = cm
(b) Assume these lenses are now combined to make a microscope; if the magnification needs to be $25\times,$ how long would the microscope be? cm
