The test scores for students who took the SAT (without the essay) are normally distributed with a mean score of 1051 and a standard deviation of 211.

The test scores of four students selected at random are 1050, 960, 870, and 1440.

In Exercises 39 and 40,

(a) find the z-score that corresponds to each value and

(b) determine whether any of the values are unusual.