For each situation, state the null and alternative hypotheses: (Type "mu" for the symbol????

, e.g.mu>>1for the mean is greater than 1,mu<<1for the mean is less than 1,mu not = 1for the mean is not equal to 1.

a) The diameter of a spindle in a small motor is supposed to be 4.3 millimeters (mm) with a standard deviation of 0.19 mm. If the spindle is either too small or too large, the motor will not work properly. The manufacturer measures the diameter in a sample of 47 spindles to determine whether the mean diameter has moved away from the required measurement. Suppose the sample has an average diameter of 4.38 mm.

b) Harry thinks that prices in Caldwell, Idaho, are lower than the rest of the country. He reads that the nationwide average price of a certain brand of laundry detergent is $18.25 with standard deviation $1.56. He takes a sample from 37 local Caldwell stores and finds the average price for this same brand of detergent is $15.76.