P is the principal; that's the amount you start with. The r is the interest rate. This is a decimal; in other words, if the interest rate is 9%, we use .09 in the equation. The n is the number of times the interest compounds each year. Finally, t is the time in years of the deposit or borrowed money.
Juan needs to create a questionnaire that adequately measures secondary traumatic stress so that his research study is valid. Secondary traumatic stress is the content domain in Juan's study. Content domain is the body of knowledge, skills or abilities being measured or examined by a test, experiment or research study.
Definition of Domain. Domain: The set of all possible input values (commonly the x variable), which produce a valid output from a particular function. It is the set of all values for which a function is mathematically defined. It is quite common for the domain to be the set of all real numbers since many mathematical functions can accept any input.