A certain metabolic reaction takes the form A B. Its standard free energy change is 7.5

Question:

A certain metabolic reaction takes the form A → B. Its standard free energy change is 7.5 kJ ∙ mol-1.
(a) Calculate the equilibrium constant for the reaction at 25°C.
(b) Calculate ∆G at 37°C when the concentration of A is 0.5 mM and the concentration of B is 0.1 mM. Is the reaction spontaneous under these conditions?
(c) How might the reaction proceed in the cell?