Please answer with a fully detailed solution with examples.
In Java, write a method to determine if a string contains onlydigit characters.
In Java, write a method on how to find each occurrence of a lettergiven a string.
In Java, given a list of numbers, write an algorithm to find allthe triples and pairs of numbers in the list that equal exactly13.
In Java, write a function to find the total number of eachcharacter in a given string.
