Problem 4.1 As illustrated in Figure 4.49, consider an 80 kg person preparing to dive into a pool. The diving board is rep-resented by a uniform, horizontal beam that is hinged to the ground at A and supported by a frictionless roller at D. B is a point on the board directly under the center of gravity of the person. The distance between A and B is = 6 m and the distance between A and D is d = 2 m. (Note that one-third of the board is located on the left of the roller support and two-third sis on the right. Therefore, for the sake of force analyses, one can assume that the board consists of two boards with two different weights connected at D.) If the diving board has a total weight of 1500 N, determine the reactions on the beam at A and D.