Which Statement represents the correct interpretation of this equation?

Use set builder notation to represent the following set: { -3, -2, -1, 0}

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.

Acyclist bike x distance at 10 miles per hour .and returns over the same path at 8 miles per hour.what is the cyclist average rate for the round trip in miles per hour ?