Penny started a business that sells flower barrettes called Penny Blossoms. Penny asks Sheldon to help her improve her manufacturing process, so they sing while working in order to increase productivity.
Inez and Digit have the key to escape the cave, and they need to get it to Jackie and Matt in order to escape. There is a huge block of ice blocking the two groups, so they decide that bouncing the key against a wall is the only option. They get one chance to bounce the key or they can lose it, so Inez uses a drawer that Digit found to test the angle that would send the key to Jackie and Matt. During the process, they learn about how angles of reflection work.