Aline passes through the points (p, a) and (p, -a) where pand a are real numbers and p#0. describe each of the
following. explain your reasoning.
1. slope of the line
2. equation of the line
3. yintercept
4. slope of a line perpendicular to the given line

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.