２０、The following appeared in a memo from the president of a company that builds and sells new homes in Steel City. "Over the past five years, the population of Steel City has increased by more than 20 percent, and family incomes in Steel City have risen much faster than the national average. Nationwide, sales of houses priced above $150,000 have increased more than have sales of lower-priced houses. Such data indicate that we should make changes in our business to increase company profits. First, we should build fewer low-priced houses than we did last year and focus instead on building houses designed to sell at above $150,000. Second, we should hire additional workers so that we can build a larger total number of houses than we did last year."