6. Which of the following is true?
a) \( K>1, \Delta G^{\circ} \quad \) rxn is positive
c) \( \Delta G^{\circ}{ }_{\mathrm{rxn}}=0 \) at equilibrium
b) \( K<1, \Delta G^{\circ} \quad \) rxn is negative
d) \( \Delta G_{\mathrm{rxn}}=0 \) at equilibrium
e) None of the above are true