20. The density of an object is related to its mass and volume. The equation below shows the relationship between density (d), mass (m), and volume (V).
m
d = = ý
Which equation represents the volume of an object in relationship to its density and mass?
a. V = d - m
b. V = dm
C. V = 0
m
d. V =
=
m
d

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?