A manufacturer of chocolate chips would like to know whether its bag filling machine works correctly at the 439 gram setting. Is there sufficient evidence at the 0.05 level that the bags are underfilled? Assume the population is normally distributed. State the null and alternative hypotheses for the above scehario. Answer 2 Points

8. For a class project, a political science student at a large university wants to estimate the percent of students who are registered voters. She surveyed 190 students and finds that 80 are registered voters. Compute a \( 98 \% \) confidence interval for the true percent of students who are registered voters and interpret the confidence interval. (Round the answers to 4 decimal places.)

Using the Pearson correlation coefficient to analyze the relationship between two variables is only appropriate if the variables are__ variables. one scale and one nominal ordinal nominal scale

Coffee consumption has been found to be negatively correlated with amount of sleep, with a correlation coefficient of 0.5 . How much can the coffee consumption account for the variance of amount of sleep? \( 0.5 \% \) \( 50 \% \) \( 0.25 \% \) \( 25 \% \)

\begin{tabular}{l} In a re-analysis of published studies, Twenge and Im (2007) found that for the \\ time period 1958-2001, the need for social approval of people in the United \\ States was negatively correlated with the U.S. divorce rate during the same \\ period (the correlation coefficient was -0.38). This correlation means that _- \\ divorce rates were high when the need for social approval was high \\ the need for social approval spurred people to divorce \\ the need for social approval prevented people from seeking divorce \\ divorce rates were low when the need for social approval was high \\ \hline\end{tabular}

Se obtuvieron los siguientes resultados para el punto de ebullición, en grados Celsius, de un compuesto de silicio: \( \mathbf{1 6 6} \), \( \mathbf{1 4 1 , 1 3 6 , 1 5 3 , 1 7 0 , 1 6 2 , 1 5 5 , 1 4 6 , 1 8 3 ,} \) \( \mathbf{1 5 7 , 1 4 8 , 1 3 2 , 1 6 0 , 1 7 5 y} \mathbf{1 5 0} \). Utilice la prueba de Kolmogorov- Smirnoff con un nivel de significancia de \( \mathbf{0 . 0 1} \) para probar la hipótesis nula de que los puntos de ebullición provienen de una población normal con una media \( \boldsymbol{\mu = 1 6 0}{ }^{\circ} \mathrm{C} \) y una desviación estándar \( \boldsymbol{\sigma = 1 0 ^ { \circ }} \mathrm{C} \)