John is auditing MegaCorp. He finds an accounts payable for 10,000 cases of ball bearings. He checks to make sure the paper actually arrived and that the receiving department signed and dated the invoice. He also checks the original purchase order to make sure the purchase was properly authorized. This illustrates

A. tracing.
B. vouching.
C. following.
D. monitoring.

By 2020, automobile market analysts expect that the demand for electric autos will increase as buyers become more familiar with the technology. however, the costs of producing electric autos may increase because of higher costs for inputs (e.g., rare earth elements), or they may decrease as the manufacturers learn better assembly methods (i.e., learning by doing). what is the expected impact of these changes on the equilibrium price and quantity for electric autos?