Please help me with these science questions about ecology!

Circle the letter of the choice that best completes the statement or answers the question.
11. Energy that is lost at each trophic level of an ecosystern is replenished by
a. heat.
b. nutrients.
sunlight
c. sunlight
d. organisms.
12. Besides energy, what moves through the organisms at each trophic level of an ecosystem?
a. organisms
b. nutrients
c sunlight
d. cycles
13. Evaporation and condensation a part of the
a. carbon cycle.
b. nitrogen cycle.
c phosphorus cycle.
d. water cycle.
14. Plants lose water to the air through
a. condensation
b. photosynthesis.
c. Their roots.
d. evaporation
15. Animals lose water when they
a. breathe in
b. urinate.
c breathe out
d. both b and c.
16. The major process by which water in the atmosphere is returned to the earth is
a. precipitation
b. evaporation
c. photosynthesis.
d. decomposition.
17. Autotrophs and heterotrophs use carbon-containing molecules for energy and for
a photosynthesis.
b. growth.
c decomposition
d. both a and b.
18. What do plants use in photosynthesis to make carbon-containing molecules?
a carbon dioxide
b. carbohydrates
c. fertilizer
d. oxygen
19. Heterotrophs get carbon-containing molecules by
a. making the molecules themselves.
b. feeding on other organisms.
c decaying.
d. growing.
20. When decomposers break down the carbon-containing molecules in dead organisms,
a. the dead organisms are converted to coal.
b. oxygen is released.
c carbon dioxide is released.
d. carbon dioxide is converted to energy-rich
carbon-containing molecules.