if a tree casts a shadow of 16ft at the same time that a 5ft person casts a shadow of 3 ft find the height of the tree

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? 0.62 0.78 0.84 0.96