Is carbon dioxide a reactant

No

Explanation: Reactants are the substances present at the beginning of a chemical reaction. In the burning of natural gas, for example, methane (CH4) and oxygen (O2) are the reactants in the chemical reaction. Products are the substances formed by a chemical reaction. In the burning of natural gas, carbon dioxide (CO2) and water (H2O) are the products formed by the reaction.

it's filtration, but this is an assumption so my apologies if i got this

for step 7 table c on the lab "newtons law of action"   the average time it took the car to travel .25 meters   was 1.92 seconds.

the average time it took the car to travel 0.50 meters was 2.61 seconds

hope this : )