The number of squirrels in a certain ecosystem changes over time. These changes can be represented as a number of connected data points. Which method would a student most likely use to show this information? OPTIONS:
- pie chart
- line graph
- pictogram
- data table
A: line graph

Which characteristic below most likely accounts for our limited knowledge of galaxies? OPTIONS:
- their tiny size
- their magnetic cores
- their inability to produce light
- their great distance from Earth
A: their great distance from Earth

Which of the following is the best estimate of the number of stars in a typical galaxy? OPTIONS:
- tens
- hundreds
- thousands
- billions
A: billions

A student is visiting a local limestone quarry and finds fossils of seashells. The quarry is located hundreds of miles from the ocean. The fossils best indicate that OPTIONS:
- this area was once below sea level.
- global temperature changed over time.
- erosion took place after a flood.
- volcanic activity affected the area.
A:
this area was once below sea level.