Answer:
a. Jake has made a unilateral contract with Mrs. Martin and a bilateral contract with the hardware store.
Step-by-step explanation:
Note that a unilateral contract occurs between Jake and Mrs. Martin because in business law this contract is created by an offer (the $100 to be paid) which is then accepted through performance (by Jake mowing the lawn).
Next Jake purchases a lawnmower from a hardware store in which a transfer of title for the lawnmower occurs (a bilateral contract). According to business law it is a case of bilateral contract because something of specific of value is exchanged; meaning $60 is paid to transfer ownership of the lawnmower .