Why was the Cambrian explosion significant in terms of the fossil record?

Which was the largest mass extinction event in Earth’s history?

50-year floods occur precisely every 50 years.

Which of the following metamorphic rocks would represent the lowest metamorphic grade?

In your own words, what is the difference between earthquake magnitude and intensity?

Which of the following is a potential sink (or output) of sand in a beach sand budget? Select all that apply

The Sun exerts the greatest tide generating force because it has more mass than the Moon. 

Which of the following is NOT a factor that promotes dune growth and stability?

•A threat assessment examines how these threats could affect the particular asset, organization, or system you are looking at, in context. With that, a threat assessment could be done on one of several levels, either simultaneously or separately.

Your goal is to study the algae that lives in the low tide zone and you want to visit the beach when the tides are lowest. When would you do it?