A dance studio charges $17 for the first ballet class a dancer takes and $11 for each class after that. What are the first four terms of an arithmetic sequence in which an is the total amount a dancer pays, in dollars, for taking n ballet classes?.

What percentage of the earth's water is available for use by living things?

Which statements are true for invasive species? 1. they always stabilize an ecosystem. 2. they’re always successful in adjusting to a new habitat. 3. they often compete with the native species for resources. 4. they have the ability to displace the native species. 5. they’re always pests.

Aconstruction crew was made up of 88 men and the rest women. if 40% of the crew were men, how many people were in the crew?