Brenda is a purchasing agent for Commodity Sales Corporation. Dennis, a Commodity Sales corporate officer, gives Brenda written authority to buy for the firm as many computers and peripheral devices as necessary. The next day, Dennis calls Brenda and tells her to buy only fifty notebook computers and nothing else. Brenda shows the written authority to Eagle E-Products, Inc., and enters into a contract with Eagle to buy sixty notebook computers and a selection of printers, scanners, and extra storage media. Eagle ships the order to Commodity Sales. Is Commodity Sales liable to Eagle under the contract? Is Brenda liable? In each case, if so, why? If not, why not?