A machine called a barometer is what is used to measure atmospheric pressure :D
It has a double C=C bond so that means it's unsaturated, but it can also be a cyclic compound with only simple C-C bonds
You forgot to attach the text
BTW reduction is the action or fact of making a specified thing smaller or less in amount, degree, or size.
To know the answer, compare the oxidation number of the element in the reactant and the product side. The oxidation number of Al was originally +3, then became 0 after the reaction. On the other hand, Fe was originally 0, then became +2 after the reaction. When the element is oxidized, it oxidation number increases. <em>Thus, the element oxidized is Fe.</em>