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July 19, 2021 at 7:24 pm #10312

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The correct answer is

**D. P(z<-a) + P(-a<z<a) + P(Z>a)**

**Explanation:**

This expression represents all of the possible values in a curve, or in other words, the total area of a curve. According to a standard normal distribution, the total area of a curve is always equal to 1 as it is a probabilistic distribution.

- This reply was modified 3 years, 1 month ago by ProtonsTalk.
- This reply was modified 3 years, 1 month ago by ProtonsTalk.