Answer:
When you open the bottle, there is a dramatic decrease in pressure over the liquid, so the CO2 starts to leave the liquid very rapidly, causing the mass exodus of gas, or "explosion" of bubbles. This also explains why soda goes flat.
Explanation: HOPE THIS HELPS YOU..
The pencil attached to the negative terminal of the battery collects hydrogen gas while the one connected to the positive terminal collects oxygen.
Fe(s) + CuSO4(aq) -> Cu(s) + FeSO4(aq) is the answer if you get it in advance...
The plants without any fertiliser could be the control, to see what the change in the independent variable (fertiliser) does to the growth of the plant (dependant variable).
Hope that helps.