Use the law of syllogism to draw a conclusion from the given information. given: if two lines are perpendicular, then they form right angles. if two lines meet at a 90 angle, then they are perpendicular. two lines meet at a 90 angle. a. conclusion: the lines are parallel. b. conclusion: the lines are perpendicular and meet at a 90 angle. c. conclusion: the lines meet at a 90 angle. d. conclusion: the lines form a right angle.

Evaluate the expression for the given value of the variable 7a - 4a for a =8

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.

You have 12 balloons to blow up for your birthday party. you blow up 1/3, and your friend blows up 5 of them. what fraction of the baloons still need blowing up