Differential profit $($loss$)$ ?is the

a$.$ ?difference in income from one year to the next.

b$.$ ?difference between the differential revenue and the differential costs that are expected from a course of action compared to an alternative.

c$.$ ?amount of increase or decrease in cost that is expected from a course of action compared to an alternative.

d$.$ ?amount of increase or decrease in revenue that is expected from a course of action compared to an alternative.