# Castle siege

You are a barbarian invading a castle. Your particular specialty is aiming the catapults. Your catapult, which can launch boulders from the ground at a speed of $$50~\mbox{m/s}$$, is $$100~\mbox{m}$$ from the castle wall, which is $$10~\mbox{m}$$ high. On top of the wall is a castle guard, waggling his fingers at you and yelling "Nyah, nyah, can't get in here!". What angle in degrees with respect to the horizontal should you launch your boulder at so that it hits the guard right between his eyes, which are $$1.75~\mbox{m}$$ above the top of castle wall?

Details and assumptions

• The acceleration of gravity is $$-9.8~\mbox{m/s}^2$$.
• Ignore air resistance.
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