Is the lateral area of a cylinder a triangle?

Step-by-step explanation:

For a right circular cylinder of radius r and height h, the lateral area is the area of the side surface of the cylinder: A = 2πrh. For a pyramid, the lateral surface area is the sum of the areas of all of the triangular faces but excluding the area of the base.

c.

step-by-step explanation:

she should of added 9^2 and 12^2. that is because it is a^2+b^2=c^2. c^2 is the hypotenuse and should always be bigger than the other two numbers. which is why she should of added 9 squared and 12 squared together instead of 15 squared.

$54.99

step-by-step explanation:

$54.99 includes 500 min. if she does not exceed 500 min then her bill is $54.99