Q: What happens when the blood cannot reach the heart because a blood vessel is blocked? Choices: - fast heart beat - heart burn - pass out - heart attack A:
heart attack

Q: Why do microwaves have a higher energy than radio waves? Choices: - higher resonance - lower frequency - higher decibel - higher frequency A:
higher frequency

Q: Q: Kidneys, large intestine, liver, skin, and lungs comprise which system? Choices: - Muscular system - Digestive system - Lymphatic system - excretory system A:
A: excretory system

Question: Q: Mechanical energy can also usually be expressed as the sum of kinetic energy and what other kind of energy? Choices: - reflective energy - directional energy - partial energy - potential energy A:
Answer: potential energy

*Question*
Q: What catalyst substances may also allow reactions to occur by different pathways that have lower activation energy? Choices: - carbohydrates - hormones - calories - enzymes A:
**Answer**
enzymes

Q: Q: What are the earth's two poles called? Choices: - southwest and south - east and west - west and south - north and south A:
A: north and south