Answer:
The answer to your question is: number 1
Explanation:
Third law of Newton: says that for every action ,there is an equal and opposite reaction.
So, if the child is pushing an object to the right, it will recipe the same amount of force that he is exerting to the object but in opposite direction.
Number 2 and 3 are incorrect because, because the third law of Newton says "an equal and opposite reaction", not slightly more or less.
Number 4 is wrong, it is not in agreement with Newton's third law of motion.
The correct option is this: THE CONCENTRATION OF THE PRODUCTS AND THE REACTANTS DO NOT CHANGE.
A reversible chemical reaction is said to be in equilibrium if the rate of forward reaction is equal to the rate of backward reaction. At this stage, the concentrations of the products and the reactants remain constant, that is, there is no net change in the concentration even though the reacting species are moving between the forward and the backward reaction.