Complete the square
to find the vertex
of this parabola.

y^2+4x - 2y+21=0

What is the volume of the sphere shown below with a radius of 3?

Do, h = (7, 9) (14, 18) the scale factor is

Which of the following would be a reasonable estimate for the weight of a pencil? a. 1 × 10^-20 lb b. 1 × 10^20 lb c. 1 × 10^2 lb d. 1 × 10^-2 lb