How many electrons in an atom may have the folling quantum numbers?
(a)`n=4,m_s=-(1)/(2)`
(b)n=3,l=0

Explanation

(a) For n=4
Total number of elctorns =`2n^(2)2xx16=32`
Half out these will have`m_s=-(1)/(2)`
`therefore`Total electrons with `m_s(-(1)/(2))=16`
(b) For n=3
`l=0,m_l=0,m_s=+(1)/(2),-(1)/(2)("two "e^(-))`