1) Serving at a speed of 170 km/h, a tennis player hits the ball at a height of 2.5 m and an angle below the horizontal. The service line is 11.9 m from the net, which is 0.91 m high. What is the angle o such that the ball just crosses the net? Will the ball land in the service box, whose outline is 6.40 m from the net?​