I think the answer is mutualism.
because mutualism means that the two species benefit each other.
You forgot to add pictures ..
<u>Answer:</u> The reactant ratio in the given chemical equation will be: 
<u>Explanation:</u>
Mole ratio is defined as the ratio of the amount of moles of two substances that are participating in a chemical reaction.
In the given chemical equation:

The reactants are Fe and
and the product is 
The mole ratio is basically the stoichiometric ratio of the chemical compounds taking part in a chemical reaction.
The mole ratio of reactants is stoichiometric ratio of Fe and
, which is:

Hence, the reactant ratio in the given chemical equation will be: 
Salutations!
Determine the length of the object shown below.
The length of the scale is 5.6 cm.
Hope I helped.