Calculate the degree of unsaturation in the following formulas, and draw five possible structures for each:
(a) $\mathrm{C}_{10} \mathrm{H}_{16}$
(b) $\mathrm{C}_8 \mathrm{H}_8 \mathrm{O}$
(c) $\mathrm{C}_7 \mathrm{H}_{10} \mathrm{Cl}_2$
(d) $\mathrm{C}_{10} \mathrm{H}_{16} \mathrm{O}_2$
(e) $\mathrm{C}_5 \mathrm{H}_9 \mathrm{NO}_2$
(f) $\mathrm{C}_8 \mathrm{H}_{10} \mathrm{ClNO}$