The answer is b. It is separating the two adjectives that are describing the customer.
He always tries or wants to pay them back in some sort of way. For example, when Nick invited Daisy over for the tea party, Gatsby tried to get him involved in something that would help him make more money. It shows that Gatsby probably feels like he is less than enough which would lead him to believe that he needs to give people a reason he is important enough for a favor.
First ask yourself what is in the hundredths place?
The 5
Then ask yourself what is to the right of that digit?
A 0, because .15=.150
Since the 0 is not bigger than a 5, the 5 in the hundredths place stays the same.
The answer is .15
A. Helps the author tell the story in the most effective way.
