Please solve using Java ASAP and write a fully answered, optimized, and detailed code with comments and screenshots along with an approach on how to solve it and why that approach, and time/space complexity along with the why. 1. Find the number of repetitive words from a given line 2. Write a function to find all prime numbers less than n 3. Write a program/function that returns only unique characters in a string 4. Write a program/function that returns the number in the middle of a list 5. Write a program/function that counts the frequency of a word in an array