What 1930 tariff law deepened the Great Depression by restricting international trade?

Smoot-Hawley Tariff

What's the imaginary line that divides Earth into Eastern and Western hemispheres? What do you call a friendly ghost from cartoons? Stollen, traditionally eaten during German holidays, originates from which city? Who was the Greek mathematician responsible for the theorem relating to right triangles? Which colonial city was famously founded by Roger Williams for religious freedom?