Input: Answer this question:
The Moon is visible to observers on Earth because of
OPTIONS:
- reflected sunlight
- absorbed light from Earth's atmosphere
- gases in the Moon's interior
- volcanic eruptions on the Moon's surface
Answer: reflected sunlight

*Question*: Scientists use models that show the features of an atom. A scientist should use a model that OPTIONS:
- was the first to be developed
- was most recently developed
- shows the arrangement most clearly
- shows the details needed for a specific purpose
*Answer*: shows the details needed for a specific purpose

question:
All plants and animals have mechanisms that
OPTIONS:
- transport nutrients
- perform photosynthesis
- regulate nerves
- produce flowers

answer:
transport nutrients

[Q]: Which is considered a nonrenewable resource?
===
OPTIONS:
- oil
- soil
- food
- water
****
[A]: oil

question below:
In a healthy forest, dead trees and limbs fall to the ground and decompose. Which of these statements best describes why decomposition is important to a forest ecosystem?
OPTIONS:
- Nutrients are released when wood is broken down.
- Worms produce oxygen used by other organisms.
- Dead trees provide nest sites for many different species of birds.
- Water is stored in dead trees and limbs.
answer below:
Nutrients are released when wood is broken down.

question:
Two pure substances combine to make a new substance. The new substance cannot be physically separated and has a different boiling point than each of the original substances. This new substance can best be classified as
OPTIONS:
- an atom.
- a mixture.
- an element.
- a compound.

answer:
a compound.