Why are experimental investigations the best type of scientific investigation to demonstrate cause-and-effect relationships? please help lol

Answer/Explanation:

Experimental investigations are the best type of scientific investigation to demonstrate cause-and-effect relationships because they allow the investigator to actively manipulate variables and control conditions. This change can be measured to gather evidence to support or refute the cause-and-effect relationship. Experimental investigations also use a control group a group that does not receive the factor being tested for comparison.

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.