Professor Himes announces that she plans on selling the answers to Exam 1 at a very reasonable price of $500.00. Kate gives Professor Himes a check for the stated amount. Professor Himes
a. is bound to sell the answers to Exam 1 to Kate because Kate accepted Professor Himes' offer. b. is bound to sell the answers but can require Kate to pay in cash to avoid a paper trail. c. may refuse to accept Kate's check because she only expressed an intent to do something in the future. d. may refuse to accept the check, because she expressed only an opinion as to the worth of her exam answers.