12. [-/2 Points] DETAILS SPRECALC7 3.1.060. A rancher with 750 ft of fencing wants to enclose a rectangular area and then divide it into four pens with fencing parallel to one side of the rectangle. (a) Find a function that models the total area of the four pens. A(W) = (b) Find the largest possible total area of the four pens. ft 2 13. [-/2 Points] DETAILS SPRECALC7 3.1.052. A ball is thrown across a playing field from a height of h = 3 ft above the ground at an angle of 45 to the horizontal at the speed of 20 ft/s. It can be deduced from physical principles that the path of the ball is modeled by the function 32 (20) 2 X2 + x+ 3 where x is the distance in feet that the ball has traveled horizontally. (a) Find the maximum height attained by the ball. (Round your answer to three decimal places.) ft (b) Find the horizontal distance the ball has traveled when it hits the ground. (Round your answer to one decimal place.) ft 14. [-/2 Points] DETAILS OSPRECALC1 3.2.143. Find the dimensions of the rectangular corral producing the greatest enclosed area given 280 feet of fencing. (Assume that the length is greater than or equal to the width.) length ft width