in this exercise, we estimate the rate at which the total personal income is rising in the richmond-petersburg, virginia, metropolitan area. in 1999, the population of this area was 961400, and the population was increasing at roughly 9200 people per year. the average annual income was $30593 per capita, and this average was increasing at about $1400 per year. use the product rule and these figures to estimate the rate at which total personal income was rising in the richmond-petersburg area in 1999. explain the meaning of each term in the product rule.