Concept:The angle of depression equals the angle of elevation from the boat to the man, so use the tangent ratio in a right-angled triangle.Explanation:Let x be the distance of the boat from the base of the tree.The height of the tree is 150 cm.Using tanθ=adjacentopposite, we have:tan74∘=x150Rearrange to solve for x:x=tan74∘150x=3.4874150x≈43.01 cmTherefore, the boat is about 43 cm from the base of the tree.Answer:B. 43 cm