A gun fires a shell at an angle of elevation of 30* with a velocity of 2000ms-1.(A)what is the range of the shell.

2 answers

time in air:
hf=hi+2000sin30*t-4.9t^2
hf=hi=0
t=2000sin30/4.9

range:
d=2000*cos30*timeinair
the fine article in wikipedia on "trajectory" explains this and more. The formula for the range is

R = v^2/g sin(2θ)