What is the balanced equation and the deltag of the coupled

Question

Examine the following reactions:

Reaction 1. Glycerol 1-phosphate + H2O ---> Glycerol + P(i)               (delta)G = -9

Reaction 2.   ATP + H2O ---> ADP + P(i) + H+                                    (delta)G = -30

What is the balanced equation and the (delta)G of the coupled reaction?

a. Glycerol 1-phosphate + ADP + H+ --->  Glycerol + ATP                    (delta)G = -21

b. Glycerol + ATP -----> Glycerol 1-phosphate + ADP + H+                  (delta)G = -21

c. Glycerol 1-phosphate + ADP + H+ ---> Glycerol + ATP                     (delta)G = -39

d. Glycerol + ATP ------> Glycerol 1-phosphate + ADP + H+                 (delta)G = -39