What’s the correct answer for this?

How many solutions does the nonlinear system of equations graphed bellow have?

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?

If my mom gets $13.05 an hour, and she works from 3: 30 to 10: 45 in the morning, how much money does my mom make?