Answer:
0.7560 seconds
Step-by-step explanation:
The height of the cliff is 20 m.
The angle of projectile = 18°
The initial horizontal speed = 12 m/s
The formula to apply is :
T= {2*v*sinθ} /g where;
T= time of flight of an object given initial launch angle θ and initial velocity v.
g= acceleration due to gravity
T= {2*12*sin 18°} / 9.81
T= {24 * 0.30901699437}/9.81
T= 0.7560 seconds