Because they are farther across the periodic table<span />
The answer should be D, cells can only create an identical copy of the original cell.
I believe the answer is A (it was on another Brainly question as well).
The answer is b. radon-222. The alpha decay means that it will emit an alpha particle when decays. The alpha particle has two protons and two neutrons. So Radium(88) minus two protons will become Radon(86). And the atomic mass will become 226-4=222.
