Amachine coats metal spheres with a plastic coating. the metal spheres have a radius of 9 mm. the spheres formed by the metal and plastic coating have a radius of 12 mm.
how much plastic coating is on each sphere?
use 3.14 to approximate pi and express your final answer in hundredths.

Afarmer has a large field that is x feet in length. he wants to fence in a rectangular section in the middle of the field , leaving a length of 100 feet of open field behind each end of the fenced rectangle.he also wants the width of the fenced-in space to be 100 feet less than its length. find the expressions to represent the length and width of the fenced section of the field