A string orchestra consists of 15 violins, 8 violas, 7 cellos, and 4 double
basses. A chamber orchestra consisting of 8 violins, 4 violas, 2 cellos and
2 double basses is to be chosen from the string orchestra.
(i) In how many ways can the chamber orchestra be chosen?
[ii] Once the chamber orchestra is chosen, how many seating arrangements
are possible if each instrument group has their own set of chairs?
(iii) The violinists work in pairs. How many seating arrangements are
possible for the violinists if they must sit with their partner?