The first item I bought or thinking of buying is a cell phone. The cell phone is exists in an Oligopoly market structure. Cell phones are an Oligopoly becuase if I wanted to start up my own cell phone company, it would be relatively hard. Also the number of firms in the cell phone field are limited and few. The cell phone products are also differentiated products, so this fits the definition of an Oligopoly.
The second item is a microsoft computer. This exists in a monopoly because there are few to none opposing businesses. I have never heard any other business that does the same thing as Microsoft. Therefore, there is no competition and making the business a monopoly.
The third item is a soda can. This exists in a Perfect Competition because there are many soda businesses and all have equal competition with one another. I think that the soda all depends on the peoples' likes and different sodas may appeal to different people. Therefore, I wouldn't buy Pepsi but instead buy a bottle or can of Fanta.
The fourth item I would choose to buy would be a jetski. This item would exist in an Oligopoly because the number of firms or businesses are few. Trying to open my own business selling jetskis would be fairly hard and would be very competitive with the few top businesses. Therefore, the jetski would be in an Oligopoly.
The fifth item that I bought was a watch. This item exists in a Perfect Competition because there are many companies that sell watches and at various prices. There are many firms and businesses that make watches, therefore making the watch existant in a Perfect Competition.