During World War I, the Germans had a gun called Big Bertha that was used to shell Paris. The shell had an initial speed of 1.86 km/s at an initial inclination of 52.2◦ to the horizontal. The acceleration of gravity is 9.8 m/s^2.

Question

During World War I, the Germans had a gun called Big Bertha that was used to shell Paris. The shell had an initial speed of 1.86 km/s at an initial inclination of 52.2◦ to the horizontal. The acceleration of gravity is 9.8 m/s^2. 
a. How far away did the shell hit? Answer in units of km.
b. How long was it in the air? Answer in units of s.

Steve · Answer

you know that (a) R = v^2/9.8 sin2θ (b) h(t) = v*sinθ - 4.9t^2 solve for h=0