Assume that the readings on the thermometers are normally distributed with a mean of \( 0^{\circ} \) and standard deviation of \( 1.00^{\circ} \mathrm{C} \). A thermometer is randomly selected and tested. Draw a sketch and find the temperature reading corresponding to \( \mathrm{P}_{86} \), the 86 th percentile. This is the temperature reading separating the bottom \( 86 \% \) from the top \( 14 \% \).

16. Bob made a picture graph of the marbles he and his friends have. How many more marbles does Bob have than Kayla? Explain ho you found the answer.

\#7 A set of data has correlation coefficient \( r \). For which value of \( r \) would the average magnitude of the residuals be the smallest? a. \( r=-0.034 \) b. \( r=0.472 \) c. \( r=0.908 \) d. \( r=0.952 \)

\#2 A survey was taken comparing the number of hours per week students spent studying and their performance on an exam. If a linear regression was performed and the correlation coefficient was -0.017 , what can be said about these results? a. As the number of hours spent studying increases, student exam performances will likely not change. b. As the number of hours spent studying inrceases, student exam performances will probably increase. c. As the number of hours spent studying increases, student exam performances will probably decrease. d. There is little evidence of a linear relationship between the number of hours spent studying and student exam performances.

1. Estas interesado en detectar diferencias en tiempo promedio de programación de comerciales en horario estelar. Un estudio similar detecto una desviación estándar de 30 minutos. Quisieras calcular una muestra con una confiabilidad del \( 95 \% \) y un error máximo tolerable de 5 minutos en tus estimaciones. ¿Qué tan grande tiene que ser tu muestra?

In a class, there are 750 learners in 1st year, 420 learners in 2 nd year. Draw a pie graph to represent the numbers of learners in these groups.