Ashley eats two bananas during a particular day. The marginal benefit she enjoys from eating the second banana

a$.$

can be thought of as the total benefit Ashley enjoys by eating two bananas minus the total benefit she would have enjoyed by eating just the first banana.

b$.$

determines Ashley$’$s marginal cost of the first and second bananas.

c$.$

does not depend on how many bananas Ashley has already eaten.

d$.$

cannot be determined unless we know how much she paid for the bananas.