There are many different products that are in demand for teenagers
             today. Normally at different times there are different products that are high
             in demand. Usually you will not see a product in high demand for a long time.
             Products come in and out with style. Whatever is in at the time is usually
             what is high in demand. And as soon as the product is no longer considered
             cool or trendy, the product usually loses its demand.
             C.D.'s for an example is something that has, and always will be in high
             demand with teenagers. Normally a product will go out of demand when
             consumers buy too much of a product (marginal utility) they get sick of it.
             Too much of something is normally not good. But C.D.'s are not the same
             product. Each C.D. has a different band or singer on it, so buying too many
             C.D.'s doesn't effect your desire to buy them, because every C.D. has
             something different on it to offer you. So therefore Marginal Utility plays a
             great factor in the demand of C.D.'s, because you buy them for satisfaction,
             and you won't get sick of buying them, because each one has something
             different to offer you. Income effect also plays a great role in the demand
             of C.D.'s. If the price of C.D. changes we have the choice to purchase more
             C.D.'s if we want to. Substitution effect also plays a role in the demand of
             C.D.'s. If for some reason we can not afford to purchase a C.D. we can always
             purchase a tape instead. Tapes are cheaper to buy, and they usually contain
             everything that a C.D. would have on it.
             Purchasing C.D.'s is quite easy today. You can go to almost any type of
             store and they sell C.D.'s, just on Long Island alone, we have stores like
             Target, Circuit City, Sam Goody, Record Town and plenty of other privately
             owned stores that sell C.D.'s. Then you can even go onto the Internet and
             purchase C.D.'s at such web-sites such as CDNOW.com and many other web-sites.
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