Describe three methods used to purify water at a water treatment plant

sodium (na), for example, has one electron in its valence shell. this is an unstable state because that valence shell needs eight electrons to be full. in order to fill its valence shell, find a way to add seven electrons to its valence shell

i believe the answer is c. "baking" is the gerund, while "baking blueberry muffins" would be the gerund phrase. hope this ! : )