Answer Happy

please any help for question 3 4 and 5
3. Find the number of derangements of AABBCC. Use the method of 04.22.2022. 4. Find the number of permutations of (n) whose disjoint cycle structures are products of 3 cycles and 5 cycles. Use the method of 04.25.2022. 5. Simplify Σ a+b+c=n a € {1,2,3,4,...) be {1,2,3,4,... } ce {1,2,3,4,... }