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The annual rainfall in a certain region is approximately normally distributed with mean 41.3 inches and standard deviation 5.6 inches. Round answers to the nearest tenth of a percent. W) What percentage of years will have an annual rainfall of less than 43 inches? 62.6 What percentage of years will have an annual rainfall of more than 38 inches? w) What percentage of years will have an annual rainfall of between 37 inches and 42 inches? Suestion Help: Read Rideo Message instructor Submit Question

Which of the following statements are TRUE about the normal distribution? Check all that apply. The area to the left of a z-score plus the area to the right of that same z-score will always equal 1 . A data value with z-score \( =-1.5 \) is located 1.5 standard deviations below the mean. The Empirical Rule only applies when a value is exactly 1,2 , or 3 standard deviations away from the mean. A z-score is the number of standard deviations a specific data value is from the mean of the distribution.

i1. suggerie a fair price for this brand. Create a \( 95 \% \) confidence interval for prive of chocolate whate percentage

Find the median of these numbers.

3. Box and Whisker Plot: Draw a box and whisker plot for the data provided and identify any outliers. \( 12,17,13,14,12,16,18,29,15,14,12,17,13,14,12,16,18,29,15,14,12,17,13 \), \[ 14,12,16,18,29,15,14 \]

3. Box and Whisker Plot: Draw a box and whisker plot for the data provided and identify any outliers. \( 12,17,13,14,12,16,18,29,15,14,12,17,13,14,12,16,18,29,15,14,12,17,13 \), \( 14,12,16,18,29,15,14 \)

2. Scatter Plot and Correlation: Consider the following data points representing the number of hours studied \( (x) \) and the marks obtained \( (y) \) : \[ (1,50),(2,55),(3,60),(4,65),(5,75) \] wa scatter plot and determine whether the relationship between hours studied and marks ositive, negative, or none.

What does the magnitude of a correlation coefficient indicate about the variables in a correlational study? Multiple Choice strength of the variables relationship between the variables number of data points

20. Some researchers claim that herbal supplements such as ginseng or ginkgo biloba enhance human memory. To test this claim, a researcher selects a sample of \( n=25 \) college students. Each student is given a ginkgo biloba supplement daily for 6 weeks and then all of the participants are given a standardized memory test. Scores on the normalized test are \( \mu=70 \) and standard deviation of 15 . The sample of 25 students had a mean score of \( M=75 \). (8 points) a. Do the data indicate a significant effect of the herb on memory? Use a two-tailed test with \( \alpha=0.05 \). (Show all steps.)

You wish to test the following claim \( \left(H_{a}\right) \) at a significance level of \( \alpha=0.002 \). \[ \begin{array}{l}H_{a}: \mu_{1}=\mu_{2} \\ H_{a}: \mu_{1}>\mu_{2}\end{array} \] You believe both populations are normally distributed, but you do not know the standard deviations for either. However, you also have no reason to believe the variances of the two populations are not equal. You obtain a sample of size \( n_{1}=20 \) with a mean of \( M_{1}=51.3 \) and a standard deviation of \( S D_{1}=13.2 \) from the first population. You obtain a sample of size \( n_{2}=23 \) with a mean of \( M_{2}=38.8 \) and a standard deviation of \( S D_{2}=8.7 \) from the second population.