Answer:
The statement is FALSE.
Explanation:
In genetics, expressivity refers to the amount of variation in a non binary phenotype across individuals, who are carrying a specific genotype. Scientists believed that variable expressivity is controlled by different factors such as environment, genetics and lifestyle choice. An example of expressivity is a series of blue eye color that has different shades of blue. Thus, expressivity is not about balanced genetic output but varied genetic expression.
Scientists establish the age of a rock or fossil based on natural radioactive decay and certain elements such as potassium and carbon, this is used to make reliable “clocks” to date ancient events.
(Sorry if not all is accurate hope it helps)