Answer:
19
Explanation:
The mass of an atom is found in the nucleus: number of protons + number of neutrons; 9 + 10 = 19
The mass number of fluorine is 19
Answer:
its false
Explanation:
since the penny is thrown straight up its not going to move forwad with you and the bus since it has no forces pushing on it. If the bus wasn't moving it would land back on your hand
Cell membrane can also be called plasma membrane
A pure substance because it cannot be separated into parts