(a) Phosphorus (P):
Atomic number = 15
The electronic configuration of P is: $1{\mathrm{s}}^2 2{\mathrm{s}}^2 2{\mathrm{p}}^6 3{\mathrm{s}}^2 3{\mathrm{p}}^3$
The orbital picture of P can be represented as:

From the orbital picture, phosphorus has three unpaired electrons.

(b) Silicon (Si):
Atomic number = 14 
The electronic configuration of Si is: $1{\mathrm{s}}^2 2{\mathrm{s}}^2 2{\mathrm{p}}^6 3{\mathrm{s}}^2 3{\mathrm{p}}^2$
The orbital picture of Si can be represented as:

From the orbital picture, silicon has two unpaired electrons.

(c) Chromium (Cr):
Atomic number = 24
The electronic configuration of Cr is: $1{\mathrm{s}}^2 2{\mathrm{s}}^2 2{\mathrm{p}}^6 3{\mathrm{s}}^2 3{\mathrm{p}}^6 4{\mathrm{s}}^1 3{\mathrm{d}}^5$
The orbital picture of chromium is:

From the orbital picture, chromium has six unpaired electrons.

(d) Iron (Fe):
Atomic number = 26
The electronic configuration is: $1{\mathrm{s}}^2 2{\mathrm{s}}^2 2{\mathrm{p}}^6 3{\mathrm{s}}^2 3{\mathrm{p}}^6 4{\mathrm{s}}^2 3{\mathrm{d}}^6$
The orbital picture of chromium is:

From the orbital picture, iron has four unpaired electrons.

(e) Krypton (Kr):
Atomic number = 36
The electronic configuration is: $1{\mathrm{s}}^2 2{\mathrm{s}}^2 2{\mathrm{p}}^6 3{\mathrm{s}}^2 3{\mathrm{p}}^6 4{\mathrm{s}}^2 3{\mathrm{d}}^{10} 4{\mathrm{p}}^6$
The orbital picture of krypton is:

Since all orbitals are fully occupied, there are no unpaired electrons in krypton.