Question 11
Carl has a house and he extends it for his warehouse, as shown in the diagram below. One day, he connects the point $A$ with a plastic tube to point $B$ which is centrally placed on the visible side of the warehouse, and is situated 1 m below the flat roof. What is the length of the shortest plastic tube, in m, required to join $A$ and $B$ if it is always to remain in contact with the surfaces of the building?
