Abe tested 85 Brand X light bulbs to determine their life spans. The histogram below shows the results of his test. Approximately what percent of Brand X light bulbs had life spans greater than or equal to 1000 hours?

A-25%

B-66%

C-85%

D-60%

Simone claims the initial value and y-intercept are the same thing on a graph. is she correct? if you know that a line has a slope of and a y-intercept of 7, what is the equation for that line in slope-intercept form?

Which inequality has a dashed boundary line when graphed ?

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.