1. A * * 14 book, when choosing the first book, there are14 possibilities, and there are 13 possibilities left in the second book, so the possibility should be 14* 13, but there are two books. Choose a and b, or

2. The idea is the same as the previous question. There are five possibilities for the first one, four possibilities for the second one, and finally we have to divide by two, so one ***5×4÷2= 10.

This is fifth-grade mathematics, so don't engage in any permutation and combination. It is the principle of multiplication directly.