26) In a bilateral contract, the consideration for each promise is ________. A) An acknowledgement B) An agreement C) A completed act D) A return promise E) The beginning of action in acceptance, even if it is not complete 27) Carrie promises Tim she will clean his house and in exchange, Tim promises to pay Carrie $50. This is an example of what type of contract? A) A bilateral contract B) An implied contract C) A contract created through promissory estoppel D) A unilateral contract E) An invalid contract  28) Tim promises to pay Carrie $50 to clean his house and Carrie comes over and cleans is house. Tim and Carrie have. A) A contract not supported by consideration B) A unilateral contract C) An implied contract D) A bilateral contract E) An invalid contract 29) In a unilateral contract, the consideration for a promise is a[n] . A) Agreement B) Consideration C) Action D) Return promise E) Acknowledgement 30) What is a key difference between a bilateral and a unilateral contract? A) Only a bilateral contract requires consideration. B) Only a unilateral contract requires consideration. C) The adequacy of consideration. D) The type of consideration. E) The existence of promissory estoppel in bilateral contracts only.  Â