These scientists all study first source artifacts from prehistoric peoples, including fossils, archaeological digs, etc. By observing and analyzing these objects, they are able to infer how these prehistoric peoples lived before there was any written record.
The responses of China and Japan to Western Imperialism were similar in several significant respects. Each nation, for centuries, successfully held back Western incursions into their territories and economies. Both China and Japan were ultimately able to maintain this policy of isolationism until the 19th century, when each finally succumbed to external pressures, though to differing degrees
It would be that the OSHA has authority over the employers of "<span>A. state government workers," although it should be noted that the OSHA also has a wide authority over many other types of employers. </span>
From what I've seen, it's true.