Answer: the structure of an atom: At the center of the atom, there is a very small region called the nucleus. This area makes up most of the mass of the atom.
The area around the nucleus is called the electron cloud. This area makes up the majority of the volume of the atom. The electron cloud is mostly empty space.
Explanation: Hope this helps :)
try it first then do it over again until it works
Answer:
air is drawn into the lungs
lungs expand
the muscles between the ribs contract to move the ribs up and down
air pressure in the chest cavity decreases
the diaphragm contracts and flattens
Answer:
false
Explanation:
a microscope is used to enhance small objects like cells.