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. Remove duplicate characters from a string 2. Find Common characters of 2 strings 3. Remove duplicates in an array of strings 4. Get the n-th Fibonacci number 5. Check whether a given string is an anagram or not