`{:(,"ColumnI",,"ColumnII"),((A),"Orbital angular momentum of an electron",(P),sqrt(s(s+1))(h)/(2pi)),((B),"Angular momentum of an electron in an orbit",(Q),sqrt((n(n+2)))),((C),"Spin angular momentum of an electron",(R),(nh)/(2pi)),((D),"Magnetic moment of atom",(S),sqrt((l(l+1)(h)/(2pi)))):}`

Answer

A-s; B-r; C-p; D-q

Explanation

`L = sqrt(l(l+1)) (h)/(2pi) mvr =(nh)/(2pi)`
Spin angular momentum `= sqrt(s(s+1)) (h)/(2pi)`
Magnetic moment `mu_(s) = sqrt(n(n+2))`