This document defines perimeter, circumference, and area of different shapes. It provides the following formulas: Perimeter is the distance around a figure and is calculated by adding all the side lengths. Circumference is the distance around a circle and is calculated using the formula C=πd, where d is the diameter. The area of a rectangle is calculated by multiplying its length and width (A=l×w). The area of a triangle is half the product of its base and height (A=1/2bh). The area of a circle is the product of π and the square of the radius (A=πr^2).