We confirm the time of t = 13.2583 sec and range of 2812.5 ft for our trajectory with our angle of elevation a = Pi/4 .

Input := 


hittime=Solve[y[t,Pi/4]==0,t]//N

x[t,Pi/4]/.hittime[[2]]//N

Output =


{{t -> 0}, {t -> 13.2583}}

Output =


2812.5