Express the null hypothesis and the alternative hypothesis in symbolic form. use the correct symbol (mu, p, sigma) for the indicated parameter. the manufacturer of a refrigerator system for beer kegs produces refrigerators that are supposed to maintain a true mean temperature, mu, of 48degreesf, ideal for a certain type of german pilsner. the owner of the brewery does not agree with the refrigerator manufacturer, and claims he can prove that the true mean temperature is incorrect. a. upper h 0: munot equals48degreesf upper h 1: muequals48degreesf b. upper h 0: mugreater than or equals48degreesf upper h 1: muless than48degreesf c. upper h 0: muless than or equals48degreesf upper h 1: mugreater than48degreesf d. upper h 0: muequals48degreesf upper h 1: munot equals48degreesf