Which of the following statements regarding the warming of the troposphere (i. e., the lower atmosphere) are true (choose all that apply):
a conduction only warms the shallow layer of air within a few centimeters of the ground
b the troposphere is heated mainly from above
c atmospheric gases do not readily absorb solar radiation
d the troposphere is heated mainly by direct molecule-to-molecule contact
e condensation of water vapor plays a role in heating the lower atmosphere
f oxygen and nitrogen readily absorb and emit terrestrial radiation
g convection distributes heat vertically