Tammie contracted with Kristine to manufacture, sell, and deliver to Kristine and put in running order a certain machine. After Tammie set up the machine and put it in running order, Kristine found it unsatisfactory and notified Tammie tht she rejected the machine. She continued to use it for three months but continually complained of its defective condition. At the end of the three months, she notified Tammie to come and get it. Has Kristine lost her right (a) to reject the machine? (b) to revoke acceptance of the machine?