Donald's utility function is U(x, y) x  y^1/2.Currently he is buying some of both goods.If his income rises and prices don't change, he will buy more of both goods.

Utility Function

This represents how consumer preferences can be quantified based on different levels of consumption of various goods and services.

Income Rises

An increase in the amount of money earned by an individual or household, which can affect consumption patterns and demand for goods and services.