A rain gutter is to be constructed of aluminum sheets 12 inches wide. After marking off a length of 4 inches from each edge, this length is bent up at an angle 0. The area
of the opening may be expressed as the function: A(O) = 16 sin 0 - (cos 0 + 1). If 0 =
30°, what is the area of the opening? (6 points)
O 14.9 in 2
O 16.0 in2
O 19.3 in 2
O 20.8 in2