[Q] Freshwater biomes contain water that contains little to no what?
Options:
- (A) cations
- (B) Acids
- (C) Nutrients
- (D) sodium
- (E) Pollution
- (F) animals
- (G) plants
- (H) water
[A] Here's my solution: Freshwater biomes have water that contains little or no salt. Another name for salt is sodium. Freshwater biomes have water that contains little or not sodium. The answer is (D).

[Q] What can stay hidden in a hibernating state inside the body?
Options:
- (A) infections
- (B) blood cells
- (C) fungi
- (D) insects
- (E) viruses
- (F) honeybees
- (G) plasma
- (H) barnacles
[A] Here's my solution: Some viruses live in a dormant state inside the body. When ferns are dormant it is as if they are hibernating. Some viruses live in a hibernating state inside the body. The answer is (E).

[Q] Phytoplankton have a clever way of making food from what?
Options:
- (A) sunlight energy
- (B) water energy
- (C) heat energy
- (D) heat produced
- (E) chemical energy
- (F) mechanical energy
- (G) organic matter
- (H) refraction of light
[A] Here's my solution: Phytoplankton are bacteria and algae that use sunlight to make food. Plants have a very clever way of using the energy from sunlight to make their food. Phytoplankton have a clever way of making food from sunlight energy. The answer is (A).

[Q] What does not grow through cell division?
Options:
- (A) p53
- (B) AIDS
- (C) host
- (D) DDT
- (E) lung
- (F) HIV
- (G) corn
- (H) HPV
[A]
Here's my solution: Populations of viruses do not grow through cell division because they are not cells. Where most viruses are DNA, HIV is an RNA virus. Populations of HIV do not grow through cell division because they are not cells. The answer is (F).