If you know the unit prices of two different brands of an item, you are better able to:
A. Determine which of the two brands is higher quality
B. Figure out the discount during a sale on the two items
C. Compare the prices of the two brands
D. Estimate how much of the item you will need

When cell phones were first entering the market, they were relatively large and reception was undependable. all cell phones were essentially the same. but as the technology developed, many competitors entered, introducing features unique to their phones. today, cell phones are only a small fraction of the size and weight of their predecessors. consumers can buy cell phones with color screens, cameras, internet access, daily planners, or voice activation (and any combination of these features). the history of the cell phone demonstrates what marketing trend?