Answer:
The demand for Xbox One games falls
The demand for Xbox One games increases
The quantity demanded on Xbox One increases
Explanation:
Xbox one , PlayStation 4, and Wii U can be referred to as substitute goods.
Substitute goods are goods which can be used or consumed in place of one other. If the price of PlayStation 4, and Wii U falls, consumers would increase the quantity demanded of this games and reduce demand for Xbox one because Xbox One is now more expensive relative to the other games.
If consumers income increase, they would have a higher disposable income and so demand would increase.
If the number of people writing and producing XBox One games increases, supply of Xbox one games would exceed demand. This would lead to a fall in price and an increase in the quantity demanded.
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