Elizabeth is a high school basketball player. In a particular game, she made some free throws (worth one point each) and some two point shots. Elizabeth scored a total of 16 points and made twice as many free throws as two point shots. Graphically solve a system of equations in order to determine the number of free throws made, x, x, and the number of two point shots made, yy.

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.