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In each of the following questions, determine whether the given measurement is a statistic or a parameter (a) The 2010 census counted 332,600,000 people in the United States [ans-a] (b) The average age of students in only one of five statistics classes is 19.8 years old.. [ans-b]

A student wants to see if there is a relationship between average overnight sleep (in hours) and number of absences a student has in a semester. In other words, can overnight sleep explain the number of absences. She collects the following sample data.Overnight Sleep (hours): 4  4  5  6  7  7  8  9Number of absences:      9  8  7  6  6  5  4  2 (a) If she constructs a scatter diagram of the data, which variable label would be on the y-axis?     (b) How many dots will be shown in the scatter diagram?   (c) Suppose the dots roughly follow a straight edge from the upper left corner (Northwest) to the lower right corner (Southeast) of the graph; what type of relationship (out of the four primary relationships) exists between the variables?   (d) Using fractional notation, what is the mean of overnight sleep (include units)?   (e) Using fractional notation, what is the standard deviation of overnight sleep (include units)?   (f) What is the IQR of overnight sleep?  Are there any outliers? If so identify them. Regardless show your work.   (g) Who is relatively more different than their peers, a student whose overnight sleep is 7 hours, or a student with 4 absences?  Show your work.

Consider the following sample data: Weight (pounds) # of Baskets 2.0 – 3.9 4 4.0 – 5.9 3 6.0 – 7.9 5   (a) What is the class width?  Show your work.      (b) What is the midpoint of the last class?  What would be the x- axis value of the right tie-down of a frequency polygon?    (c) If the shape of the frequency polygon has a longer tail to the left of the peak than to the right of the peak, what shape is it?   (d)  What is the mean of the data, answer using fractional notation?  

A student surveys the first 40 students that depart the University bookstore. Is it likely the survey results will not have a bias?

To which step in the statistics process would sampling every 3rd washing machine on a production line belong?  Name the step.

A researcher separates students into groups and tests them at various exercise levels in order to determine the impact on their health.  Which of the following is this?

Which type of sampling method is illustrated in the previous problem?

In each of these statements, write whether the variable is qualitative, quantitative-discrete or quantitative-continuous. (a) The number of people in an auditorium.  (b) The flavors of candy in a bag.

Las noticias de hoy. Osvaldo is reading the paper, and Jimena reacts to all the headlines. Complete her comments using the elements given and the past subjunctive.  Follow the model. ​MODELO      Asesinaron a un importante empresario. Si yo (investigar) investigara  el asesinato, hablaría con los empleados.   Hubo una gran erupción volcánica. Si (haber)_________ una erupción volcánica aquí, nuestros amigos no (saber) ____________  qué hacer.

​El resultado de las manifestaciones…​