$\mathrm{Na} / \mathrm{K}$ pumps transports
(a) $3 \mathrm{Na}^{+}$ out for $2 \mathrm{~K}^{+}$ in
(b) $3 \mathrm{Na}^{+}$ in for $2 \mathrm{~K}^{+}$ out
(c) $2 \mathrm{Na}^{+}$ out for $3 \mathrm{~K}^{+}$ in
(d) $2 \mathrm{Na}^{+}$ in for $3 \mathrm{~K}^{+}$ out