Enter the correct answer in the box. Help me out please

99 points at a zoo, the leopard pen has a ring-shaped sidewalk around it. the outer edge of the sidewalk is a circle with a radius of 12 m. the inner edge of the sidewalk is a circle with a radius of 8 m. (1 point for showing all of your work) a. write and simplify an expression for the exact area of the sidewalk. (1 point for the answer) b. find the approximate area of the sidewalk. use 3.14 to approximate π. (1 point for the answer)

What is the solution to the system of the equations? x = y - 3 x + 3y = 13

Statement: if two points are given, then exactly one line can be drawn through those two points. which geometry term does the statement represent? defined term postulate theorem undefined term