7. (10 pts) You have 100 feet of fencing to build a pen in the shape of a circular sector, the "pie slice" shown below. The area of such a sector is equal to rs/2. What value of r maximizes the area of the sector? S r 8. (10 pts) What value of b minimizes the sum of the squares of the vertical distances from y = 2x + b to the points (1, 1), (1, 2), and (2,2)? 3-1 y = mx + b 2-+ b 2