The lifetimes of a particular brand of DVD player are normal

The lifetimes of a particular brand of DVD player are normally distributed with a mean of eight years and standard deviation of six months. Find each of the following probabilities where x denotes the lifetime in years. In each case, sketch the probability. P(7 less than or equal to x less than or equal to 9) P(8.5 less than or equal to x less than or equal to 9.5) P(6.5 less than or equal to x less than or equal to 7.5) P(x greater than or equal to 8) P(x less than or equal to 7) P(x greater than or equal to 7) P(x less than or equal to 10) P(x greater than 10)

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