Two friends Ryan (R) and Sabrina (S) are running and their distance and time are shown in the graph. The time is shown in minutes in the x-axis and the distance covered is shown in miles in the y-axis. How much faster was Ryan running than Sabrina per hour?

Determine whether the following statements are true and give an explanation or counterexample. bold a. when using the shell method, the axis of the cylindrical shells is parallel to the axis of revolution. bold b. if a region is revolved about the y-axis, then the shell method must be used. bold c. if a region is revolved about the x-axis, then in principle it is possible to use the disk/washer method and integrate with respect to x or the shell method and integrate with respect to y.

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The standard deviation for a set of data is 5.5. the mean is 265. what is the margin of error?