Through electrical impulses
Manipulative experiments alter levels of a predictor variable (or factor), and then measures how one or more variables respond to these alterations. ... Natural experiments-An observational study in which we take advantage of natural variation that is present in the variable of interest.
Answer:
8
Explanation:
Hydrogen has 1 Valence electron, and H2O has 2 Hydrogen. Oxygen has 6 Valence electrons so do 2+6 = 8. 8 Valence electrons! (Or one full shell not consisting of the first shell.)