Help pls I have a test

Simplify. (-2)^-3 a. -8 b. -1/8 c. 1/8 d. 8

You are standing next to a really big circular lake. you want to measure the diameter of the lake, but you don't want to have to swim across with a measuring tape! you decide to walk around the perimeter of the lake and measure its circumference, and find that it's 400\pi\text{ m}400? m. what is the diameter dd of the lake?

Which aspect of electronic commerce does the ftc regulate? a. encryption and transfer of data b. disposing of credit reports c. network security d. antivirus software updates