The ratio that forms a proportion with /

Solve the equation - 2(m -30) = -6m a-15 b-13 c-8 d8

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.

Awindow has the shape of a rectangle with a semi circle at the top. find the approximate area of the window using the dimensions shown. 4ft by 8ft