A. A reason for the increased use of electricity is the increasing population; more people are being born, more people are using electricity.
b. A strategy to reduce the amount of fossil fuels is for more people to use electric cars where the electricity is sourced naturally. Perhaps the government could implement a system where drivers of electric cars could be rewarded.
The growth of the plants is the dependent variable, the stuff added to each plant is the independent variable, the plants that don't receive treatment/other stuff are control variables.
