During which stage of planetary development did the lunar maria form?

During which stage of planetary development did the lunar maria form?
 
  a. cratering
 b. differentiation
 c. flooding
 d. tectonic plate movement
  e. slow surface evolution

Question 2

During the Sun's main-sequence lifetime, ____.
 
  a. the solar wind will remove about 50 of the Sun's total mass
 b. the solar wind will remove about 10 of the Sun's total mass
 c. the solar wind will remove 1-2 of the Sun's total mass
 d. the solar wind will remove a tiny fraction of the Sun's total mass
 e. mass loss from the solar wind will be balanced by material falling onto the surface from the corona

Question 3

Which was the source of lava during the flooding stage of the Moon's development?
 
  a. moonquakes and tectonic shifts
  b. lower crust and upper mantle
 c. the deep core
 d. volcanoes
 e. impacts

Question 4

A medium-mass star evolves into a red giant because ____.
 
  a. the core expands as new fusion products collect there
 b. the surface of the star becomes cooler
 c. energy from hydrogen shell burning and helium fusion forces the outer layer to expand
  d. the surface of the star becomes hotter
 e. increased stellar winds carry large amounts of material off of the surface of the star

Question 5

What was the purpose of the LCROSS mission?
 
  a. To determine if lava still flowed beneath the crust
 b. To generate an altitude map of the Moon's surface
 c. To photograph geological features of the Moon
 d. To photograph geological features of the Moon
 e. To determine if there is water ice buried in soil of the Moon's south pole