Concept:Use tanθ=adjacentopposite by taking the horizontal distance between the wall and the tree as the base.Explanation:Let the horizontal distance between the wall and the tree be x.Let the height of the tree be h.The tree is taller than the wall, so the vertical difference between their tops is h−24.From the bottom of the tree, the top of the wall is seen at an angle of elevation 30∘.Therefore, tan30∘=x24.This gives x=243. From the top of the tree, the top of the wall is seen at an angle of depression 60∘.So, tan60∘=xh−24.Substitute x=243:3=243h−24h−24=243×3=72h=96 mAlso, x=243=24×1.732=41.56 m.Thus, the required distance is 41.56 m and the height of the tree is 96 m.