$(5$ pt$)($a$)$ Consider the oxidation of malate to phosphoenolpyruvate $($PEP$)$ and $C{O}_2$ by $NA{D}^{+}$:

Malate $+NA{D}^{+}+GTP$PEP$+C{O}_2+GDP+$NADH$+H^{+}$

Given the thermodynamic data and the intracellular concentrations of reactants and products below, calculate $G$

at $pH=8\mathrm{.}1$ and $37C$ for the reaction shown below $($which takes place in the mitochondrial matrix$)$

$GTP+H_{2}OGDP+P_i+H^{+},G^{\text{@}1}=-32\mathrm{.}2k\frac{J}{m}ol$

Oxaloacetate $+P_i+H^{+}$PEP$+C{O}_2+H_{2}O,G^{\text{@}1}=+33\mathrm{.}4k\frac{J}{m}ol$

PEP$+H_{2}O$ pyruvate $+P_i,G^{\text{@}1}=-61\mathrm{.}9k\frac{J}{m}ol$

Steady$-$state intracellular concentrations: