Suppose Amy's wage (W) is $6 an hour, her non-labor income (V) is $15 a day, consumption C is measured in dollars, and she has 18 hours in the day to work (h) or leisure (L). The equation of her budget constraint is:
a. C = 123-6L.
b. C = 123-6h.
c. C = 108-6L.
d. C = 108-6h.
e. none of the above.