It has been suggested that occupational exposure to benzene in the petroleum industry increases the risk of developing leukemia. the levels of benzene to which workers in this industry have been exposed were high from 1940 to 1970, but since 1970 have been significantly reduced. what kind of study design, using petroleum workers, would provide the most useful information on whether benzene affects incidence rates of leukemia in this industry? you may assume that records of individual worker assignments to jobs involving benzene exposure have been maintained by the industry.

(a) experimental
(b) retrospective cohort
(c) prospective cohort
(d) case-control
(e) cross-sectional

According to justice brown's opinion, social equality must be the result of what three factors?

John lennon and paul mccartney belonged to this group

The persians landed in the plains near athens. as their army greatly outnumbered that of the greeks, the greeks hoped to find aid from nearby sparta. a long-distance runner named pheidippides was sent from athens to sparta to request , but the spartans were not able to send more soldiers at the time. regardless, the greeks were still able to win the battle. centuries later, legend developed that a runner had been sent from the battle to athens after the greek victory. after reaching athens, the runner proclaimed, "we are victorious! " and then fell to the ground and died. this legendary story is the inspiration for the modern long-distance runs that are performed today. this passage refers to the events of which battle during the persian wars? a. battle of thermopylae b. battle of salamis c. battle of plataea d. battle of marathon