Task_one: Determine 10 test cases which reflects the priorities of this website
Challenge 1: Get the nth number in the fibonacci sequence given n. Alternatively given a number F, print out whether it's a fibonacci number and what the closest index n in the fibonacci sequence is.
Challenge 2: Write a solution to find the character that has the highest number of occurrences within a certain string, ignoring case. If there is more than one character with equal highest occurrences, return the character that appeared first within the string. For example: Input: "Character" Output: c