The largest mass extinction in earth's history occurred at the end of which era

Which theory suggested that the earth was once a signle supercontient that gradually that broke up into the contients that we know today

If the distance between two points on the ground is 10 miles and the distance between the same two points on a map is 4 inches, what is the map scale expressed as a ratio?

Hey, i was what is consisted in a sustainable city? like what unique designs they have, etc. for answering ; )