ANYONE PLEASE ? NEED ASAP FOR A TEST

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.

When conducting research for forming a hypothesis, which practice should historians follow?

Name three new weapons that changed how ww! was fought and how?