If the wavelength of the first line in Balmer series is 6300A0, the wavelength (in A0) of the second line in the same series will be
6800
7200
4861
4700
For the first line of Balmer series
n1 =2 , n2 = 3
For the Second line of Balmer Series :
n1 = 2, n2 = 4