Can you give me the explanation,solution and answer for this?

Permutations and Combinations EXERCISE 1. There are 4 Programming and 3 Discrete Structures books on the bookshelf. Programming books should be placed on the left side of the bookshelf and Discrete structures books on the right side of the bookshelf. How many ways are there to arrange the books? 2. Nine students booked a room in a hotel. They should be accommodated in two 3- bed and one 2-bed room. In how many ways can they be accommodated? 3. In how many ways can you have a sum of 15 by 3 playing cubes? 4. In a men's volleyball team, there are 4 m. A team of nerds were used as targets. For every successful spike, the team scores 1 point and for every hit in the face, the team scores 3 points. The team needs at least 25 points to end the training session. In how many ways can the team end the training? 5. An 8 digit password is made of digits 91235564. How many possible passwords are there