A stone is thrown with speed U ms−1U \text{ ms}^{-1}U ms−1 from a point A A\,A on top of a sea cliff, 30 m above the water. The stone is projected at an angle of 45∘ 45^\circ\,45∘ to the horizontal. Point B B\,B represents the highest point in the stone's path, which is 20 m above the level of the cliff.
Find the value of UUU.
Find the horizontal distance travelled by the stone from A A\,A to the water.
Find the speed of the stone when it hits the water.
