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Explain oxidation using rust as an example

A classic example of the old definition of oxidation is when iron combines with oxygen to form iron oxide or rust. The iron is said to have oxidized into rust. The chemical reaction is: 2 Fe + O2 → Fe2O3. The iron metal is oxidized to form the iron oxide known as rust.

Explanation:

multiple allele inheritance is traits controlled by more than 2 alleles (ex: pigeons having 3 alleles of one gene govern their feather color).

one person pulls 90n one way and the other has 100n pulling the other way.

so the net force = 90 - 100 = -10n,

or the ans can be 10n if the picture shows -90n and 100n instead.