<h2>Operational </h2>
Explanation:
The operational definition is the description of a specific process, or set of validation tests, accessible to more persons than the definer (i.e., said to be publicly accessible), where it can be repeatedly measured or tested
Operational definitions are also used to define system states or (nonspecific) physical objects by the description of a specific process of preparation which can be repeated
For example in the given example experimenter is using the case of hitting a punching bag to measure the level of aggression in someone
You want about 500 calories a day extra.
Substitution mutation is when a single base pair in a strand of DNA is replaced. This can cause an early stop amino acid, or the protein could change slightly, or the protein could be unchanged completely due to there being multiple base pairs to make an amino acid.
B. Consumers depend on producers to make food using sunlight. This is the right option.