A cannon is used by the department of forestry to launch containers of fire retardant on to a fire. the cannon is at a distance of 1kilometre from a cliff that is 0.5kilometre high from the ground and the fire is 1kilometre away from the base of the cliff. if the retardant consul are launched at an angle of 45, what initial velocity is needed?

Why would the consul allow himself to be shot from a cannon? Your use of the word "are" implies there are more than one consuls.

Compute the flight time in terms of the launch velocity Vo and elevation change. Set the product of Vo cos45 and flight time equal to 1.0 km. Then solve for Vo