Answer:
Mobile homes are a substitute good.
Explanation:
Substitute goods are goods in which one of them can be used instead of the other. Their demands are related, so if a variable changes, the demand for those goods will also change. Generally the variables that give way to these changes in demand are the price of the good or the income of the consumer.
In this case, the income of consumers increased, so the demand for mobile homes decreased, this means that mobile homes are a substitute for a standard house, that is, having more income consumers will replace mobile homes by standard houses being these more expensive.
