During the second industrial revolution, which building material became one of the most important in the world?

Which of these is not a criticism of the concentric zone model? it does not accurately describe cities after the rise of suburban development. it only applies to cities that grew after the development of the automobile. it assumes that inner-city areas will always be repurposed instead of abandoned. it places too much importance on the traditional central business district.

During the age of imperialism, suez canal connected which two bodies of water?

What terms did the treaty of versailles place on germany