The shell's horizontal position
and vertical position
are given by


where
is the given speed of 1.70 x 10^4 m/s, and
is the acceleration due to gravity (taken here to be 9.80 m/s^2).
To find the horizontal range, you can use the range formula,

with
being the angle at which the shell is fired.
Alternatively, we can work backwards and deal with part (b) first:
(b) The time spent in the air is the time it takes for the shell to reach the ground. To find that, you solve for
in
:

(a) After this time, the shell will have traveled horizontally
