10. (5 points) On the basis of past history, a car manufacturer knows that 3% (p = 0.03) of all newly made cars have an initial defect. In a random sample of n = 500 recently made cars 4% (p = 0.04) have defects. (a) (3 points) Find the value of the standardized z-score for this sample proportion. (b) (2 points) Is this sample proportion unusual? Why or why not