Through which material can light waves travel but sound waves cannot travel? air metal vacuum water

The model illustrates a process by which a substance is taken up by a cell

Which of the following is not a food produced in rainforests? a) coffee b) cocoa c) avocados d) wheat

What did not occur in the proterozoic eon a)the oxygen levels increase greatly in the atmosphere, b)the emergence of the eukarya , c)muti cella’s eukaryotic organisms began to diversify, d)anaerobic bacteria kept thriving with more oxygen