I think it's B because in the question it says "she is testing the efficiency of various pH levels by measuring average growth rate". Also, keep in mind that dependent variable is what is being tested or measured in a scientific experiment. The growth of the plant would be independent variable because when testing for a independent variable it's the change or what's being controlled.
Answer:
The corect answer is some of the reactants were spilled.
Explanation:
Before the initiation of the reaction the total mass of both reactants is 15.0 grams and after the reaction the net mass of product is grams 12.4grams.
This happens because during the reaction some reactant molecules were spilled which ultimately leads to decrease the mass of the reactant molecule.
The decrease in the amount of the reactant equals with amount of product formed.
A Russian botanist and biochemist named Alexander Oparin came up with the idea that the first cells in existence might have formed from liquid droplet protocells. He assumes that the protocell can act naturally and form a container without membranes that is concentrated in chemicals
A couple of problems are erosion and the pollution of surface water and groundwater from agricultural biocides, which can decrease the water quality in nearby rivers or other water sources.
