Suppose finishing time for cyclists in a race are normally distributed and have a known population standard deviation of 6 minutes and an unknown population mean. A random sample of 18 cyclists is taken and gives a sample mean of 146 minutes. Find the confidence interval for the population mean with a 99% confidence level.

In the xy-plane, if the parabola with equation passes through the point (-1, -1), which of the following must be true?

The measure of one angle of an octagon is two times smaller that of the other seven angles. what is the measure of each angle?

This is a rational expression because the denominator contains a variable. this is a polynomial with 3 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 4 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 4 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 3 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 5 terms.