Question

You are a general in the Napoleonic war. The battle has taken you to a trench 7m deep. You have a mortar that will fire an explosive at a speed of 200 m/s at an angle of 80. You have a low flying reconnaissance airplane scouting out the enemy troops at a height of 500 m. Your pilot does not want to fly in the path of your bomb. What distance from your camp would your pilot be well advised to avoid?