A Ruby Laser Beam $\lambda$ = 6943 Nm)is Sent Outwards from a 2

Multiple Choice

A ruby laser beam ( $\lambda$ = 694.3 nm) is sent outwards from a 2.7-m diameter telescope to the moon,384,000 km away.What is the radius of the big red spot on the moon?

A) 500 m
B) 250 m
C) 120 m
D) 1.0 km
E) 2.7 km