One way to control avalanches is to send explosive charges to key areas on mountain slopes to trigger small avalanches before larger ones can build up. Norway, for instance, uses solar- powered launchers that fire pre-timed charges. Your launcher fires charges at an angle of 70 degrees from the horizontal and a speed of 200 m/s. If you fire a charge and it travels a horizontal distance of 300 m away from you, how high up the slope will it strike?.