Solve the all parts of given question:
Question: Lunar astronauts placed a reflector on the moon's surface, off which a laser beam is periodically reflected. The distance to the moon is calculated from the round-trip time.
Part A: To what accuracy in meters can the distance to the moon be determined; if this time can be measured to 0.100 ns?
Part B: What percent accuracy is this, given the average distance to the moon is 3.84 x 108 m?
Express your knowledge to solve the all parts of above question.