The formula for the future value v (in dollars) of an investment earning simple interest is v=p+prt, where p (in dollars) is the principal, r is the annual interest rate (in decimal form) and t is the time (in years). a. solve the formula for p . p= b. an investment earns 6% simple interest. what amount of principal is needed to have $3000 after 5 years? round your answer to the nearest cent. amount of principal: $