The senior classes at High School A and High School B planned separate trips to the state fair.
The senior class at High School A rented and filled 12 vans and 14 buses with 626 students.
High School B rented and filled 4 vans and 2 buses with 126 students. Each van and each bus
carried the same number of students. How many students can a van carry? How many students
can a bus carry?

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.