Avideo website would like to test the hypothesis that the standard deviation for the length of an online video watched by a user is more than 2 minutes. a random sample of 21 people who watched online videos was selected. the sample standard deviation for the length of the video was found to be 2.5 minutes. what is the number of degrees of freedom for this hypothesis test?

An automobile assembly line operation has a scheduled mean completion time, μ, of 12 minutes. the standard deviation of completion times is 1.6 minutes. it is claimed that, under new management, the mean completion time has decreased. to test this claim, a random sample of 33 completion times under new management was taken. the sample had a mean of 11.2 minutes. assume that the population is normally distributed. can we support, at the 0.05 level of significance, the claim that the mean completion time has decreased under new management? assume that the standard deviation of completion times has not changed.

Use the equation and type the ordered-pairs. y = 2 ^x

Acontainer full of water weighs 15.5 lbs. when ¼ of the water is poured out, the container now weighs 12 ½ lbs. how much does the container weigh when empty?