Indicate by a (+), (-), or (0) whether each of the following events would probably cause average annual inventory holdings to rise, fall, or be affected in an indeterminate manner. Also provide an explanation for each event and the affects.

a. Our suppliers switch from delivering by train to air freight.

b. We change from producing just-in-time to meet seasonal sales to steady, year-round production.

c. Competition in the markets in which we sell increases.

d. The rate of general inflation increases.

e. Interest rates rise; other things are constant.