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A student success office studies whether weekly tutoring hours predict final exam scores. Excel regression output gives the following: Multiple R = 0.918R Square = 0.843Significance F = 0.006Intercept = 54.327Tutoring Hours coefficient = 4.812 Which statement is correct?

A standardized reading score is normally distributed with mean μ = 72 and standard deviation σ = 8. What is the probability that a randomly selected student scores below 84?

A sales director predicts monthly sales Y using website visits X₁ and number of sales calls X₂. Excel output gives: Multiple R = 0.935R Square = 0.874Adjusted R Square = 0.846Significance F = 0.002Intercept = 14.775X₁ coefficient = 0.026X₂ coefficient = 1.384 Which statement correctly interprets R Square?

A city planner uses average household income X₁ and average commute distance X₂ to predict neighborhood retail spending Y. Excel output gives: Multiple R = 0.781R Square = 0.610Adjusted R Square = 0.557Significance F = 0.064Intercept = 12.340X₁ coefficient = 0.009X₂ coefficient = −0.415 Using α = 0.05, which conclusion is correct?

Let X follow a Poisson distribution with mean λ = 4.9. Write the Excel formula/function to compute: P(X >= 6) Use the complement of the cumulative distribution if appropriate.

A political polling firm compares the proportion of registered voters supporting a ballot measure in County 1 and County 2. Let p₁ = support proportion in County 1. Let p₂ = support proportion in County 2. The firm claims that the support proportion in County 1 is less than the support proportion in County 2. Which setup is correct?

A museum gift shop sells an average of λ = 1.8 limited-edition prints per hour. Assume sales follow a Poisson distribution. What is the probability that the shop sells at least 1 print in a randomly chosen hour? Round to 3 decimal places.

A random sample of 735 app users finds that 12.8% disabled push notifications. A 99% confidence interval will be constructed for the true population proportion. What is the margin of error E?

A two-sample mean test has H₁: μ₁ < μ₂ and α = 0.12. Enter the left [left]_____ and right [right]_____critical values. If there is no critical value enter “na”. (round to 3 decimals)

A greenhouse experiment compares plant growth using 3 fertilizer types and 2 watering schedules, with 6 plants in each fertilizer/watering combination. Excel two-factor ANOVA with replication gives: Interaction p-value = 0.018Fertilizer p-value = 0.031Watering p-value = 0.044α = 0.05 Which conclusion is most appropriate?