Simplify 4 over 7 ÷ 3 over negative 8.

Ineed with number 17 i don’t get it at alll

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.

Secant ac and bd intersect at point e inside f what is the measure of aed if measurements cd equals 30 a b is 50 and cb is 170