If the range of a gun which fires a shell with muzzle speed v, is R, then the angle of elevation of the gun is
Range of gun with velocity 'v' and angle of elevation θ
R=v2sin2θgsin2θ=gRv2θ=12sin−1gRv2
LCM of v2−v, v2−12, and v3−1
The LCM of v2−v, (v−1)2, and v3−1 is