Your parents will retire in 14 years. They currently have $290,000, and they think they will need $1 million at retirement. What annual interest rate must they earn to reach their goal, assuming they don't save any additional funds? Do not round intermediate calculations. Round your answer to two decimal places.

Four key marketing decision variables are price (p), advertising (a), transportation (t), and product quality (q). consumer demand (d) is influenced by these variables. the simplest model for describing demand in terms of these variables is: d = k – pp + aa + tt + qq where k, p, a, t, and q are constants. discuss the assumptions of this model. specifically, how does each variable affect demand? how do the variables influence each other? what limitations might this model have? how can it be improved?