Anyone understand this

The human resources manager at a company records the length, in hours, of one shift at work, x. he creates the probability distribution below. what is the probability that a worker chosen at random works at least 8 hours? probability distribution px(x) 6 hours 7 hours 8 hours 9 hours 10 hours 0.62 0.78 пол

0if x and y vary inversely and y=6 as x=7, what is the constant of variation?

Factor and solve to find roots x squared -x - 90 =0