1. By definition, IQ scores follow a normal distribution. Suppose that a specific IQ test is devised to have a mean of 100 and a standard deviation of 20. Randomly select 25 adults. (a) Determine P(X₁ > 105). (b) Determine P(X > 105). (c) Compute P(98 < X < 104). (d) Determine P(X < 100). (e) Find P(S2>240). (f) Compute P(S ≤ 18).

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