Suppose a projectile is fired from a cannon with velocity \( v _ { 0 } \) and angle of elevation \( \theta \) . The horizontal distance \( R ( \theta ) \) it travels (in feet) is given by the following.
\( R ( \theta ) = \frac { ( v _ { 0 } ) ^ { 2 } \sin 2 \theta } { 32 } \)
If \( v _ { 0 } = 80 ft \) /s, what angle \( 0 \) (in radians) should be used to hit a target on the ground \( 118 \) feet in front of the cannon?