O A. Margo leases an apartment and pays $500 cash as a security deposit when she moves in.
B. Robby pays 10 percent cash up front and gets a loan for the
remaining 90 percent of the cost of a condominium.
C. Billy orders a piano, pays half the cost up front, and has to pay the
other half when the piano is delivered.
D. Jan signs a cell phone plan that includes a little of the cost of her
new phone as part of her bill every month.