Question 1186172
Here's how to calculate the p-values for the given hypothesis test:

**Understanding the Problem**

We are conducting a one-tailed (right-tailed) z-test.  Our null hypothesis is that the average reflectometer reading is equal to 20 (μ = 20), and our alternative hypothesis is that it is greater than 20 (μ > 20).  The p-value represents the probability of observing a test statistic as extreme as, or more extreme than, the one calculated (in this case, a z-score), *assuming the null hypothesis is true*.

**a. z = 3.3**

1.  **Find the area to the right of z:** Since this is a right-tailed test, the p-value is the area under the standard normal curve to the *right* of the calculated z-score.

2.  **Use a z-table or calculator:** Look up the area corresponding to z = 3.3. Most z-tables give the area to the *left*. If that's the case, subtract the value you find from 1 to get the area to the right.

P(z > 3.3) ≈ 0.0005

**b. z = 1.6**

1.  **Find the area to the right of z:** Again, since it is a right-tailed test, the p-value is the area to the right of the given z-score.

2.  **Use a z-table or calculator:** Look up the area corresponding to z = 1.6.

P(z > 1.6) ≈ 0.0548

**Answers:**

*   a. p-value ≈ 0.0005
*   b. p-value ≈ 0.0548