Ou work as a cashier for a grocery store and earn $5 per hour. you also mow lawns and earn $10 per hour. you want to earn at least $50 per week, but would like to work no more than 10 hours per week. which system of inequalities, along with y ≥ 0 and x ≥ 0, would you use to solve the real-world problem?

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.