Answer : The volume of active ingredient present in the bottle are 0.7 mL
Explanation :
As we are give that:
5.00 % by volume means that 5.00 mL of active ingredient present in 100 mL of solution.
As, 100 mL of solution contains 5.00 mL of active ingredients
So, 14.0 mL of solution contains of active ingredients
Therefore, the volume of active ingredient present in the bottle are 0.7 mL
1) The metal which reduces the other compound is the one higher in the reactivity. So in this case it is .
2) The substance which brings about reduction while itself getting oxidised (that is losing electrons) is called a reducing agent. Here, $\mathrm{Zn}$ is the reducing agent and reduces Cobalt Oxide to Cobalt while itself getting oxidised to Zinc oxide.