Expert systems: select one: a. are capable of solving wide ranges of problems. b. are based on do while rules. c. lack the general intelligence of human beings. d. share characteristics with mainframe computing. e. are used for knowledge discovery.

Label each of the following statements true, false, or uncertain. explain your choice carefully. a. workers benefit equally from the process of creative destruction. b. in the past two decades, the real wages of low-skill u.s. workers have declined relative to the real wages of high-skill workers. c. technological progress leads to a decrease in employment if, and only if, the increase in output is smaller than the increase in productivity. d. the apparent decrease in the natural rate of unemployment in the united states in the second-half of the 1990s can be explained by the fact that productivity growth was unexpectedly high during that period.