they are made by of two types of elementary particles
electrons and quarks
quetion answered by
(jacemorris04)
Answer:
Explanation:
Food moves through the digestive system with a wave-like motion called peristalsis. Muscles in the walls of the hollow organs contract and relax to cause this movement, which pushes food through the esophagus into the stomach.Apr 25, 2018
Answer:
each of two or more forms of the same element that contain equal numbers of protons but different number of nurtrons
in there nucleir
Explanation:
.....
