#Program 8.1

(Check SSN) Write program that prompts the user to enter a Social Security number in the format ddd-dd-dddd, where d is a digit. The program displays Valid SSN for a correct Social Security number or Inval id SSN otherwise

#Program 8.4

(Occurrences of a specified character) Write function that finds the number of occurrences of a specified character in a string using the following header

def count (s, ch):

The str class has the count method. Implement your method without using the count method. For example, count ("Wel come", 'e') returns 2. Write test program that prompts the user to enter a string followwed by a character and displays the number of oceurrences of the character in the string.

#Program 8.6

(Count the leters in a string) Write function that counts the number of letters in a string using the following header:

def countLetters (s) :

Write test program that promps the user to enter a stnng and displays the number of leters in the string.