Spring agreed to buy Summer's car. Because the actual purchase was not to take place for several months, they drew up a lengthy agreement that specified all of the rights and obligations of each of the parties that they could think of. They took this two-page, single spaced document to an attorney for review. The attorney suggested a few changes. They had the documented retyped and they signed it. The contract is referred to a

a. An executed contract

b. A formal contract

c. An implied contract

d.A simple contract