15. A recent monthly press release on the Consumer Price Index says, "The Consumer Price Index for All Urban Consumers (CPI-U) increased 0.2 percent in July, before seasonal adjustment, to a level 256.6 (1982-84 = 100), the Bureau of Labor Statistics of the U.S. Department of Labor reported today." This means that a. prices have increased 256.6% so that it now costs $356.60 to buy goods and services that cost $100 in 1982-1984. b. prices have increased 156.6% so that it now costs $256.60 to buy goods and services that cost $100 in 1982-1984. c. prices have increased 0.2% so that it now costs $100.20 to buy goods and services that cost $100 in 1982-1984. d. a mistake has been made because an index number can only take values between 0 and 1