Question: Choose your answer.

Extinction of a species is most likely to occur as a result of

OPTIONS:
- evolution
- migration
- selective breeding
- environmental changes
My Answer: environmental changes

Question: Choose your answer.

On the periodic table, the elements in group 18 (8A) (helium, neon, argon, etc.) are grouped together because

OPTIONS:
- they are lighter than air.
- they have full outer electron shells.
- they have excess electrons to share.
- they easily react with other elements.
My Answer: they have full outer electron shells.

Question: Choose your answer.

Katia was listening to music on the radio. In order for the sound to be produced, the electrical energy must be converted into which type of energy?

OPTIONS:
- thermal energy
- magnetic energy
- chemical energy
- mechanical energy
My Answer: mechanical energy

Question: Choose your answer.

The distance between the Sun and the next closest star, Proxima Centauri, is most accurately measured in

OPTIONS:
- magnitudes.
- light years.
- perigees.
- red shifts.
My Answer:
light years.