(a) Four parts in a play are to be given to four of the girls chosen from the seven girls in a drama class. Find the number of different ways in which this can be done.

(b) Three singers are chosen at random from a group of \(5\) Chinese, \(4\) Indian and \(2\) British singers. Find the number of different ways in which this can be done if

(i) no Chinese singer is chosen,

(ii) one singer of each nationality is chosen,

(iii) the three singers chosen are all of the same nationality.