Equation of a line which has a slope of -1 and passes through (-2, -3)

Which expression calculates the speed in meters per second of an object that travels a distance of 100 m every 20 seconds

If the discriminant if a quadratic equation is 4 which statement describes the roots?

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.