The length of a shadow of a building is 28 m. The distance from the top of the building to the tip of the shadow is 36 m. Find the height of the building.

Solve the system of equations. y= 2x y= x^2 - 15

One positive number is 9 more than twice another. if their product is 95, find the numbers

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.