The official visual flight rules require that the distance between the ground and the bottom of the clouds to be more than 1000 feet for a plane to fly without instrumentation. at night, cloud height can be determined by aiming a searchlight straight upward and having an observer find the angle of elevation to the point at which the light hits the clouds. suppose the observer stands 400 feet away from the searchlight and sights the beam of light on the clouds with an angle of elevation 57∘. what is the height of the cloud cover?