2. A cannon with a muzzle speed of 100 m/s is used to start an avalanche on a mountain slope. The target is 250 m from the cannon horizontally, and 80 m above the cannon. At what angle, above the horizontal, should the cannon be fired? 3. A dart is thrown horizontally with an initial speed of 15 m/s toward point P, the bull's-eye on a dart board. It hits at point Q on the rim, vertically below P, 0.5 s later. (a) What is the distance PQ? (b) How far from the dart board is the dart released? 4. The certain world-record motorcycle jump is 77 m, set by Jason Renie. Assume that he left the take-off ramp at 120 to the horizontal and that the take-off and landing heights are the same. Neglecting air drag, determine his take-off speed. 5. A firefighter a distance d = 300 m from a burning building directs a stream of water from a fire hose at angle 0 = 30 " above the horizontal as shown in the figure below. If the initial speed of the stream is vi = 100 m/s, at what height h does the water strike the building? 6. You throw a ball toward a wall at a speed of 25 m/s and at an angle of 350 above the horizontal. The wall is d = 22 m from the release point of the ball. (a) How far above the release point does the ball hit the wall? (b) When it hits the wall, has it passed the highest point on its trajectory