Which amount is layer 3/5 or .41 and why

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?

Aright cylinder has a diameter of 8 m and a height of 6m. what is the volume of the cylinder

What is the area of this parallelogram? 434.28 cm2 263.67 cm2 527.34 cm2 217.14 cm2