A certain music school has 40 students, with 10 each studying violin, viola, cello, and A string quartet usually has two violins, one viola, and one cello. For this problem, we consider quartets with one of each of the four types of string instruments, but you can try to think about the situation in which there are 20 violinists, 10th violinists, and 10 cellists that are to be partitioned into traditional string quartets. string bass. The director of the school wishes to divide the class into 10 string quartets; the four students in each quartet study the four different instruments. In how many ways can this be done