Match each example to the correct definition.

a. You receive an email from someone claiming to be a Nigerian prince. In exchange for access to your bank account to facilitate a transaction, he promises to reward you financially (though the promise goes unfulfilled).
b. A parent provides food for her child without expecting repayment.
c. Bob and Stan frequently go to lunch together. Bob picks up the tab one day and expects that Stan will do so next.
d. Every two weeks, you receive a paycheck for your job. About 20 percent of your pay goes toward local, state, and federal taxes, and another small portion goes toward the federal Medicaid program to help families with low income.