What is bartering and why do more people do it today than maybe 5 years ago?

Sue peters is the controller at vroom, a car dealership. dale miller recently has been hired as the bookkeeper. dale wanted to attend a class in excel spreadsheets, so sue temporarily took over dale's duties, including overseeing a fund used for gas purchases before test drives. sue found a shortage in the fund and confronted dale when he returned to work. dale admitted that he occasionally uses the fund to pay for his own gas. sue estimated the shortage at $450. what should sue do?