OUtside a home there is a 10 key pad with letters A, B, C, D, E, F, G, H, I, and J
OUtside a home there is a 10 key pad with letters A, B, C, D, E, F, G, H, I, and J that can be used to open the
garage if the correct 10 letter code is entered. Each key may be used only one. How many codes are possible?