An algebra class has 8 students and 8 desks. For the sake of variety, students change the seating arrangement each day. How many days must pass before the class must repeat a seating arrangement?

Suppose the desks are arranged in rows of 4. How many seating arrangements are there that put Larry, Moe, Curly, and Shemp in the front seats ?

What is the probability that Larry, Moe, Curly and Shemp are sitting in the front seats? ​