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6. A publisher introduces a weekly magazine that sells for Php 395.00. The company marketers estimate that sales x (in thousand) will be approximated by the following probability distribution. X 10 15 20 25 30 35 P(x) 0.250 0.200 0.150 0.300 0.075 0.025 Find the mean, standard deviation, and expected value of the probability distribution. Interpret the results in the context of the real- life situation.3. The maximum patent life for a new drug is 17 years. Subtracting the length of time required by the FDA for testing and approval of the drug provides the actual patent life of the drug-that is, the length of time that a company has to recover research and development costs and make a profit. Suppose the distribution of the lengths of patent life for new drugs is as shown here: Years, 3 5 6 7 8 X P(x) .03 .05 .07 .10 .14 .20 Years, 9 10 11 12 13 X P(x) 18 .12 .07 .03 .01 a. Find the expected number of years of patent life for a new drug. b. Find the standard deviation of x