Answer:
any of two or more forms of a chemical element, having the same number of protons in the nucleus, or the same atomic number, but having different numbers of neutrons in the nucleus, or different atomic weights. There are 275 isotopes of the 81 stable elements, in addition to over 800 radioactive isotopes, and every element has known isotopic forms. Isotopes of a single element possess almost identical properties.
Explanation:
Going down A-D
Going across is 1-4
A 4
B 3
C 1
D 2
Hope this helps! Brainliest?
Have a great day :)
Answer:
your questions is not exactly sure but make sure your questions
Answer:
A. The tortoises will develop longer necks.
Explanation:
