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