Answer
a) 1s$^{2}$2s$^{2}$2p$^{1}$ (one unpaired electron)
b) 1s$^{2}$2s$^{2}$2p$^{6}$3s$^{2}$3p$^{2}$ (two unpaired electrons)
c) 1s$^{2}$2s$^{2}$2p$^{6}$3s$^{2}$3p$^{4}$ (two unpaired electrons)
Work Step by Step
a) 1s$^{2}$2s$^{2}$2p$^{1}$ (one unpaired electron)
b) 1s$^{2}$2s$^{2}$2p$^{6}$3s$^{2}$3p$^{2}$ (two unpaired electrons)
c) 1s$^{2}$2s$^{2}$2p$^{6}$3s$^{2}$3p$^{4}$ (two unpaired electrons)
