2. Why do you think the railroad companies made Chinese immigrants set the explosives that carved tracks through the mountains?

Ateam of scientists studied the sediment at the bottom of an ancient lake. they were able to determine the weather conditions of the indus valley in ancient times. they found that the entire area had suffered a drought after the monsoons declined. this drought lasted 200 years. because of the drought, there wasn’t enough food or water. the people of the indus valley were forced to leave their cities.

How did tyrants attempt to gain the approval of common citizens?

What are new social classes emerged due to advancement in agriculture ?