2. Gio is designing a ring for a friend. His friend wants to know the shape of the stone, and Gio tells
her that it is a quadrilateral and the diagonals of the shape bisect at right angles. Is this enough
information for Gio's friend to determine the shape of the stone? Explain your reasoning.
earning, Inc

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.