I don't know about 14, but 15 is (4), because a liquid draws in heat to turn into a gas. 16 is (2), because to turn into a cold solid, something has to release heat.
Answer:
Neutrons released during a fission reaction cause other nuclei to split
As the period number increases on the periodic table, moving from top to bottom, the atomic radius of the elements increases as well.
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The explanation is shown in the image attached with
Hey i am trying to get points so i don't really know