Whats 10.5 divided by 2.1

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?

The slope of the line whose equation is 2x - 1 = 0 is

What is being done to the variable in the equation 3 + g = -9? the number 3 is being added to it. the number 3 is being subtracted from it. the number -9 is being added to it. the number -9 is being subtracted from it.