Maria and Joe entered into a contract for the sale of Maria's car. Delivery of the car and payment were to be made on March 1. Joe advised Maria that he needed the car so that he can commute between San Francisco and Oakland to his new job that is starting on March 2. Maria broke the contract and failed to deliver the car on March 1. Joe needed a car to commute so he rented a car at $30 per day for 20 days, which was the reasonable amount of time it took him to locate and buy another car. Joe sued Maria for his losses, including the $600 car rental. With regard to the $600, what kind of damages are those?
a) liquidated
b) consequential
c) punitive
d) specific performance