The Social Security number is composed of a 3-digit area number, a 2-digit group number and a 4-digit serial number; a serial number is a unique number. Rules for assigning an SSN are quite extensive as mentioned below Area numbers can't be 000, 666 and 900-999. Group number can't be 00. Serial number can't be 0000. Please calculate: a. How many total SSNs are possible in the US? b. Is it possible to calculate the total number of SSNs possible for State of Ohio? If yes, what is that number? If no, why? (Hint: Clearly think of the counting rules which would apply to this problem and how many choices are available for each part of the SSN.)