On average, what percentage of solar energy striking the outer atmosphere eventually reaches Earth's surface?
a. 5 percent
b. 15 percent
c. 30 percent
d. 50 percent
e. 70 percent
Question 2
As ocean temperatures increase, which greenhouse gas increases and enhances the atmospheric greenhouse effect, thereby illustrating a positive feedback process?
a. nitrogen
b. oxygen
c. argon
d. water vapor
e. hydrogen sulfide