A train traveled from one city to another city in 4 hours at a speed of 70 mph. The retum trip was made in 5 hours. Find the speed for the return trip.

After being rearranged and simplified, which of the following equations could be solved using the quadratic formula? check all that apply. a. 9% + 3x2 = 14 + x-1 b. -x+ + 4x + 7 = -32-9 c. 5x + 4 = 3x4 - 2 d. 2x2 + x2 + x = 30

Solve 2x+y=3 x+y=5 in substitution method

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.