Q: The nucleus of MOST atoms consists of ---- OPTIONS:
- neutrons only
- protons and neutrons
- protons and electrons
- neutrons and electrons

A: protons and neutrons

Q: Which best explains the importance of nitrogen in the cycling of energy and matter? ---- OPTIONS:
- Nitrogen increases protein production in plants.
- Nitrogen decreases protein production in plants.
- Nitrogen decreases the effectiveness of photosynthesis.
- Nitrogen increases the effectiveness of photosynthesis.

A: Nitrogen increases protein production in plants.

Q: Harmful ultraviolet rays from the Sun are primarily absorbed by ---- OPTIONS:
- dust.
- ozone.
- land masses.
- water vapor.

A: ozone.

Q: What is the primary energy source that drives all weather events, including precipitation, hurricanes, and tornados? ---- OPTIONS:
- the Sun
- the Moon
- Earth's gravity
- Earth's rotation
A: the Sun