Maria and carla were hiking when maria tripped, fell, and sprained her ankle. carla took out the first-aid kit and unwrapped a cold pack. carla popped a vial that was inside the cold pack. the two chemicals inside the pack mixed together and the pack began to get icy cold. carla applied the pack to maria's ankle. what kind of reaction occurred in the cold pack? what evidence supports your answer? question 11 options: a. it is a physical change because the substance in the vial dissolved in the pack's liquid. b. it is a chemical change because two different chemicals are mixed together. c. it is a chemical change because heat energy is absorbed and the pack gets colder. d. it is a physical change as evidenced by a drop in temperature.