Avolcano is best defined as a. a dangerous geologic area b. the site of a violent eruption c. a chamber below-ground that is full of molten rock d. a place where some magma reaches earth's surface

The circles, or orbits, for electrons are called energy levels. each level can hold only a certain number of electrons. add electrons to each level until you can't add any more. how many electrons can each level hold?

What are some possible short and long term medical concerns for crew members on longer space exploration trips

According to theories of how life began, how did early organic molecules begin to separate from the outside world? a: specialized enzymes were required b: chains of amino acids created a barrier c: formation of microspheres or vesicles d: rna catalyzed the formation of membranes