(2) (12×0.24+0.24)×800=288,
That is, among the 800 students who participated, about 288 students won the prize; ? ... (9 points)
(3) From the flow chart, S = g1f1+g2f2+g3f3+g4f4 = 65× 0.12+75× 0.4+85× 0.24+95× 0.24 = 8/kloc-.
The value of the output s is 8 1…( 15 points).