. In a sample of H atoms, electron jump from 10^th excited state to ground state.  If ‘x’ are the number of different UV radiations, y are the number of different visible radiations and ‘z’ are the number of different infrared radiations. The value of   Z-(x+y) is
Assume all the Balmer lines lie within visible region

1. 17                           b. 18                      c. 19                       d.36