(b) The equation for computing the area of an octagon is area = 8 tanr2 where s is the length of a side, where r is the length from the center of an octagon to a vertex as shown in Figure Q3(b)(). Figure Q3(b)(i): Octagon Write a program that prompts the user to enter the length from the center of a pentagon to a vertex and computes the arca of the pentagon. The result must end with three (3) digits after the decimal point. Following in Table Q3(b)(ii) is an example of the output: Table Q3(b)(ii): Example of the Output E Enter the length from the center to a vertex: 3 Area of Regular Octagon = 29.823 [11 marks]