If an electron has spin quantum number $$ + \frac{1}{2}$$  and magnetic quantum number $$-1,$$ it cannot be present in

Solution :
Spatial orientation of the orbital with respect to standard set of cordinate axis. Magnetic quantum number $$-1$$  is possible only when the azimuthal quantum number have value $$l = 1,$$  which is possible for $$p,$$ $$d$$ and $$f$$ - subshells but not for $$s$$ - subshell because the value of $$l$$ for $$s$$ - subshell is zero.