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You have now had practice with the binomial distribution and the exponential distribution.The approach to solving problems for the normal distribution is similar to that for the exponential function, but obviously you use different R functions (usually pnorm() or qnorm()).

For the following three exercises, assume that you have a normally distributed random variable, called A, with a mean of7, and a population standarddeviation of 3.

13) What is the probability that a randomly selected value from variableAwill be greater than 9 (see Yakir, 2011 p. 88-89, 100)?_______

14) What value of variableAwould be the cutoff point (criterion value) for identifying the lowest 4% of values in variable A (use the qnorm function)?____________

15) What is the probability that a randomly selected value from variableAwill be more than one standard deviation above its mean (there are couple ways to solve this, one way is to use the standard normal distribution, Yakir, 2011, p. 90-91) ?________________