Mr. and Mrs. Jones have six kids – 3 boys and 3 girls. Today, a photographer is taking pictures of the family.
a) In how many ways can the kids be seated in a row so that all the girls are on the left and all the boys are on the right?
b) In how many ways can Jones’ kids be seated in a row so that girls and boys alternate?
c) In how many ways can the whole family be seated, if all the girls must be sitting together, all the boys must be sitting together as well, and parents must be either together in the centre, or on both sides?