There was once a tale told of WW2 in the Pacific, The Japanese were on one side of the island and the Allies were on the other with a big jungle in the middle. The question was how to go after the Japanese.
The Aussie said "just go through the jungle and get the Japanese"
The Brit said "No, we need to go around the jungle"
The American said " Naw you are all wrong! We just remove the jungle and go get them Japs"
The Aussie lisp would be just to paste this in the command line
(* pi (getreal "raduis")(getreal "radius again")(getreal "height"))
Has the additional advantage of working with truncated cones as well