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The Newark Police Department is attempting to estimate the average rate of speed on Broad Street...

The Newark Police Department is attempting to estimate the average rate of speed on Broad Street after 8:00 PM. With hidden radar, the speed of a random selection of 25 vehicles was measured, which yielded a sample mean of 42 mph and a standard deviation of 6 mph.

a. Estimate the standard error of the mean.

b. Using the same data, estimate the 95% and 99% confidence intervals for the sample mean
Math   Statistics-And-Probability   
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