[Q] Escaping poor weather and food supply changes what?
Options:
- (A) population age
- (B) the environment
- (C) population education
- (D) general preferences
- (E) important habitats
- (F) population size
- (G) movement
- (H) an organism's body
[A] Here's my solution: Migration is a type of movement that changes population size. Birds migrate to escape poor weather and food supply. Escaping poor weather and food supply changes population size. The answer is (F).

[Q] Endocrine hormones travel through the what in something that runs like water?
Options:
- (A) body
- (B) muscle
- (C) state
- (D) a path
- (E) ligt
- (F) a fish
- (G) liquid
- (H) CO 2
[A] Here's my solution: Endocrine hormones travel throughout the body in the blood. And blood, blood runs like water. Endocrine hormones travel through the body in something that runs like water. The answer is (A).

[Q] What phylum do starfish belong to?
Options:
- (A) fertile
- (B) animals
- (C) Echinoderm.
- (D) Mollusca.
- (E) Sponge.
- (F) Absorb light
- (G) Annelid.
- (H) a fish
[A] Here's my solution: Echinoderms have a unique water vascular system with tube feet. Each starfish arm is lined with tube feet. Starfish are echinoderms. The answer is (C).

[Q] Vertebrate chordates have what part of the skeletal system?
Options:
- (A) spinal column
- (B) hard bones
- (C) aerobic capacity
- (D) cartilage bones
- (E) critical organs
- (F) joints
- (G) fur and fat
- (H) graptolites
[A]
Here's my solution: Vertebrate chordates have a backbone. Invertebrates are animals who lack a backbone or spinal column. Vertebrate chordates have a spinal column. The answer is (A).