$\bullet$ A telescope is used to observe two distant point sources
transversely 2.50 $\mathrm{m}$ apart with light of wavelength 600 $\mathrm{nm}$ .
The objective of the telescope is covered with a slit of width
0.350 $\mathrm{mm}$ . What is the maximum distance in meters at which
the two sources may be distinguished if the resolution is dif-
fraction limited and Rayleigh's criterion is used?