In a game called Taxation and Evasion, a player rolls a pair of dice.X If on any turn the sum is 7,11 or 12, the player gets audited. Otherwise, she avoids taxes. Suppose a player takes 5 turns at rolling the dice. The variance of the number of times she will be audited is _____. Based on past experience, it is assumed that the number of flaws per foot in rolls of grade 2 paper follows a Poisson distribution with an average of 1 flaw per 5 feet of paper (0.2 flaw per foot). what is the probability that in a question a. 1-foot roll there will be at least 2 flaws? b. 12-foot roll there will be at least 1 flaw? c. 50-foot roll there will be between 5 and 15 (inclusive) flaws? 希望能把这两题算式都列出来 感谢 --

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