<span>the action of forming a united whole</span>
Answer:
irreversible chemical change
Explanation:
A chemical change always results in a new substance and as it is not possible to reverse it, it is an irreversible chemical change.
I hope you understood :)
<span>Cattle and sheep are exposed to lead and zinc when these poisons are in the grass/soil.
Cattle and sheep graze on the grass, and thus they intake these minerals, such as lead and zinc when they come in contact with grass or earth they may eat along with grass. Thus they are exposed to them via eating.
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