Question

The number of radial nodes of 3s and 2p orbitals are respectively

Answer 1

Radial nodes (3s) = n-l-1
                              =  3-0-1
                              = 2 

Radial nodes (2p) = n-l-1
                              = 2-1-1
                              = 0

Answer 2

the formula is :-
n-l-1
3s    s subshell:- n=3,l=0
3-0-1=2
2p    p subshell:- n=2,l=1
2-1-1=2-2=0