b2 1. Given the irregular quadrilateral, find the length of c. 02 b b = 180 m C = 115 m A = 120 A G b = 165 m Q=? Az = 100 B B A2 2. A fence enclosure consists of a rectangle of length L and width 2R and a semicircle of radius R. The enclosure will have an area, A, of 1600 ft. The cost of the fence is $40/ft for the curved portion and $30/ft for the straight sides. Find the values of R and L required to minimize the total cost of the fence. Also compute the minimum cost. 3. A torus is shaped like a doughnut. If its inner radius is a and its outer radius is b, its volume and surface area are given by: V(a,b)=0.25 *pi*(a+b)*(b-a) and A(a,b) = pi* (b-a) Calculate V(1,2), A(4,7), V(5, 8), and A(2.1, 3.5). 4. The height and speed of a projectile launched with a speed of vo at an angle A to the horizontal are given by. h(t)= vot sin(A) -0.5 gt v(t) = sqrt(vo-2vo*g*t*sin(A) +g*t) where g is the acceleration due to gravity. The projectile will strike the ground when h(t) = 0. Suppose that A = 30, vo=400 m/s, and g = 9.81m/s. a. Determine when the height is more than 15 m b. Determine when the speed is greater than 360 m/s