The relationship between the cost, y, in dollars, of x pounds of concrete can be modeled by a proportional equation. Part A The equation is y= x. Part B At this rate, how much do 150 pounds of concrete cost? Enter the answer in the space provided. $

Graph the system: f(x)= 3/x-2; f(x)= 1/2x + 2

Sanya noticed that the temperature was falling at a steady rate of 1.4 degrees every hour from the time that she first checked her outdoor thermometer. by 6 a.m., the temperature had fallen 21 degrees. which expression can you use to find how many hours earlier she had first checked the thermometer?

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.