Hyphens: Which compounds take one?

Why is a compound sometimes hyphenated and sometimes not? To find out, try your hand at our quiz!

1. The medications used to treat this condition are Placeholder for the answer.
2. Leptin is the Placeholder for the answer to appetite control.
3. Please Placeholder for the answer the equipment for the game.
4. This Placeholder for the answer gives clients a better range of choices.
5. Because it is both Placeholder for the answer, this product is a wood for all seasons.
6. Wood that is Placeholder for the answer protects against rot and insects.
7. It is a Placeholder for the answer fact that the earth is round.
8. It is a Placeholder for the answer fact that the earth revolves around the sun.
9. It is Placeholder for the answer that the earth revolves around the sun.