Suppose you have an algorithm for washing a dinner plate. The algorithm consists of:

a. Push the plate into soapy water

b. Wipe the plate thoroughly with a non-abrasive pad

c. Rinse the plate

d. Place the plate in the drain rack

You plan to add a loop to the algorithm so that it will properly handle any number of plates. Would you use a pre-test loop or a post-test loop? Why?