Adolphin is living in a closed system consisting of a large aquarium, the dolphin, and its food. which method could be used to demonstrate the law of conservation of energy? a. measure the total energy in a dolphin, the aquarium, and the food fed to the dolphin every day for 30 days. then divide by 30 to find the average energy. b. measure the energy of the food, the dolphin, and the aquarium before feeding and after feeding. determine the difference to show that energy has changed forms. c. measure the total energy in a dolphin before feeding and after feeding. the difference represents energy that has been destroyed. d. measure the energy of the dolphin after feeding to show that energy has been created.

Two students are working together on an experiment that measures the effect of different liquid fertilizers on the thickness of plants’ stems. which is most likely to result in the greatest amount of error in their scientific experiment? a.one student measures the plant stem widths by using calipers. the other student measures the widths of the same plant stems again by using a different pair of calipers. b.one student measures the plant stem widths by using calipers. the other student types the measurements as they are taken into a computer spreadsheet. c.one student weighs liquids for the experiment by using a calibrated scale. the other student weighs liquids for the experiment by using a different calibrated scale.