The code should be in Python

1. Write a function that takes two sets of strings and returns True if all elements of the first set are also in the second set.

2. Write a function that is given a list and a set returns a new list with all elements from the initial list that are also in the set. The new list must have the element appear in the same order as they do in the original list. For the elements that are in the given set the number of the occurrences of the element in the new list must be the same as the number of occurrences of the element in the original list.

3. Write a function that counts the number of vowels in a given string. Remember that the letters might be uppercase or lowercase. You might want to use a set to represent letters that would be considered vowels.