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Which measure of central tendency would be used in economics where one of the topics studied is income of Americans?

Use this information to answer the next two questions. The rates of movement of various molecules across the membrane of a eukaryotic cell were measured. The cells were then poisoned with cyanide and allowed to die, and the rates of the molecules movement across the membrane were measured again. The data are summarized in this table. Molecule tested Rate before death(mean ± standard deviation) Rate after death(mean ± standard deviation) Number of samples Potassium 35 ± 30 976 ± 88 6 Water 30 ± 28 842 ± 83 3 Carbon dioxide 1543 ± 176 1499 ± 165 9 (“Mean ± standard deviation” means that the first number represents the mean of the samples plus or minus the second number, which represents the standard deviation for those samples. This gives a range for the data, much like the error bars on a graph.)

You and another rescuer begin CPR. Your colleague begins compressions, and you notice that the compression rate is too slow. What should you say to offer constructive feedback?

You are interested in studying different types of membrane transport. Initially you stain the cells for molecule X and Y and find that they are not expressed in the cell.  You then place the cells in an isotonic solution. You add molecule X to the solution and notice that it appears to bind temporarily to the surface of the cell and then later shows up inside the cell. You add molecule Y and notice that it instead rapidly transports from outside the cell to inside the cell, without binding to the cell surface, until the concentration is balanced. What kind of transport is being described for molecule Y?

Which question most precisely reflects Jagendorf and Uribe’s question?

Engelhardt draws a line between circumstances that are simply ___________ and those that are actually _______________

A study is done to determine the average tuition that Penn State undergraduate students pay per semester. One is asked how much tuition is paid for the fall semester in the following situation: A sample of 100 undergraduate Penn State undergraduate students is taken by organizing the students’ names by classification (freshman, sophomore, junior, or senior) and then selecting 25 students from each. What type of sampling is used?

What is the standard deviation for Group B?  

You have a planar bilayer with equal amounts of saturated and unsaturated phospholipids. After recording the degree of permeability of this membrane to glucose (there was some permeability), you increase the proportion of unsaturated, kinked phospholipids in the bilayer. What will happen to the membrane’s permeability to glucose?

Determine the type of sampling used: A medical researcher interviews every third cancer patient from a list of cancer patients at a local hospital.