three friends Abbie,Boobie and Cillie orderd a jazz,country and classical CD respective.The three CD's were delivered,on

three friends Abbie,Boobie and Cillie orderd a jazz,country and classical CD respective.The three CD's were delivered,one to each of the three fried,but none got the correct CD.
(a)Determine the number of ways in which this might occur.
(b)they were joined by Doobie(who wanted a rock CD)in placing their next order.Again all four received one of the CD's orderd but again all got the wrong CD.Determine the number of ways in which this might have occurred.
(c)Before inviting pop lover Eobbie to join them the four friends decided to see in advancce what sort of risk they would be taking.they decided to construct a recurrence relation!
taking W5 to be the number of ways that all five would receive the wrong CD,express w5 in term of W4 and W3 and hence determine W5.