NHTSA crash tests. Refer to the NHTSA crash tests of new car models, Exercise 4.3 (p. 212). A summary of the driver-side star ratings for the 98 cars in the file is reproduced in the accompanying Minitab printout. Assume that one of the 98 cars is selected at random and let x equal the number of stars in the car’s driver-side star rating.

a. Use the information in the printout to find the probability distribution for x.

b. Find P1x = 52.

c. Find P1x … 22.

d. Find m = E1x2 and practically interpret the result.