5. Assume z is a standard normal random variable. P(1.20 < z < 1.85) equals A. 0.4678 B. 0.3849 C. 0.8527 D. 0.0829 6. The travel time for a businesswoman traveling between Dallas and Fort Worth is uniformly distributed between 40 and 90 minutes. The probability that she will finish her trip in 80 minutes or less is: A. 0.02 B. 0.2 C. 0.8 D. 1.0 E. none of the above 7. The life expectancy of a particular brand of tire is normally distributed with a mean of 40,000 miles and a standard deviation of 5,000 miles. What is the probability that a randomly selected tire will have a life of at least 30,000 miles? A. 0.4772 B. 0.9772 C. 0.0228 D. none of the above 8. An exponential probability distribution: A. is a continuous distribution B. is a discrete distribution C. can be either continuous or discrete D. none of the above

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