Asheet of metal is 30cm x 6m and is being used to make a rectangular eavestrough by bending along the dotted lines. what value of x maximizes the capacity of the eavestrough?

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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.

To finance her community college education, sarah takes out a loan for $2900. after a year sarah decides to pay off the interest, which is 4% of $2900. how much will she pay