#### Answer

a) 4
b) 5
c) 2
d) n=3, l=1,
Possible values of $m_{l}$= -1, 0 or +1

#### Work Step by Step

a) The number of subshells= the value of n= 4
b) Because the subshell is d, l=2. The possible values of the magnetic quantum number are -2,-1,0,1 or 2 (from -l to +l).
Total number of orbitals= Number of possible values of $m_{l}$ =5
c) Maximum value of l= n-1= 3-1= 2
d) n=3, l= azimuthal quantum number corresponding to the p subshell= 1.
Allowed values of $m_{l}$ ranges between the interval -l and +l. Therefore
$m_{l}$= -1, 0 or +1.