If y varies directly as z, and y = 19 when z = 152, find the equation of variation A. y= 1/8z
B y = 8z
C y = -1/-2 z
D y = -2x

Find the cosine function that is represented in the graph.

Match each inequality to the number line that represents its solution

Afactory makes propeller drive shafts for ships. a quality assurance engineer at the factory needs to estimate the true mean length of the shafts. she randomly selects four drive shafts made at the factory, measures their lengths, and finds their sample mean to be 1000 mm. the lengths are known to follow a normal distribution whose standard deviation is 2 mm. calculate a 95% confidence interval for the true mean length of the shafts. input your answers for the margin of error, lower bound, and upper bound.