1. Define a function that returns the number of character 'a' in a given cstring. 2. Based on Question 1, define a function that can count the number of any given character in a given cstring. 3. Define a function that checks whether a given cstring does not contain specific character. 4. Define a function that reverses a given cstring. 5. Define a function that takes a cstring str as its argument and returns a reversed copy of str. Note, for this question, str should not be changed