Use stars and bars to solve each counting problem. You may leaveyour answers as binomial coefficients.
(a) How many collections of 6 (not necessarily distinct) coinscan be made from an infinite supply of pennies, nickels, dimes, andquarters?
(b) A social security number is a sequence of 9 digits. How manysocial security numbers are there n1n2n3 . . . n9 such that ni ≤ni+1 for i = 1 to 8? For example, 024455888 would count but254180419 would not count
