Sarah class is squaring complex numbers. 3+4i^2=9-16=-7. Did Sarah square 3+4i^2 correctly

An arc subtends a central angle measuring 7pi/4 radians what fraction of the circumference is this arc?

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?

In dire need~! describe how to use area models to find the quotient 2/3 divided by 1/5. check your work by also finding the quotient 2/3 divided by 1/5 using numerical operations only.