Answer:
No, it has too many variables or possible changes.
Explanation:
If you carried out an experiment or research on something, you have to given the same environmental and soil conditions to the factors. In this experiment, Kevin put the first plant in large pot and the other two plants in the field conditions. For performing correct experiments, Kevin put all the plants in separate pots or in the field conditions.
Answer:
Most amphibians can breathe both through cutaneous respiration (through their skin) and buccal pumping - though some also retain gills as adults. Some aquatic salamanders (and all tadpoles) have gills and can breathe underwater thanks to them. The Mexican axolotl, for example, never loses its gills.