The primary producers in freshwater and salt water ecosystems are heterotrophs. true or false

Give an example of complex institution

What is another way of saying " has a high density"?

The European Union has expanded to also include some nations from Central Europe and Eastern Europe

Which plate boundary and movement commonly create volcanoes that can result in the development of habitable islands?

True or false born disease wiped out the Spanish who came to conquer the Aztecs

The Gibraltar connects what two bodies of water?

Estonia, Lithuania, Ukraine, Belarus, and Moldova once comprised Yugoslavia. True False

Where do most volcanos form A) In the ocean B) Over a hotspot C) At plate boundaries

Which of these is not an environmental effect of destroying wetlands A. loss of habitat B. increased air temperature C. poor absorption of rain water D. unfiltered water

Iron atoms combine with oxygen atoms to form rust. Is this a physical property of iron or a chemical property?