A rent ceiling is . A. a price floor in the housing market B. the opportunity cost of renting an apartment C. the mechanism that eliminates search activity in the market for low-income housing D. a government regulation that makes it illegal to charge a rent higher than a specified level

D.

Explanation:

A rent ceiling is a government regulation that makes it illegal to charge a rent higher than a specified level. Meaning that the landlord of a building cannot charge a rent amount higher than the maximum price set forth by the rent ceiling. Landlords that violate this law are usually fined by the government as a consequence.

u = 30

continuing your method

= +

subtract from both sides

= - thus

= -

= ⇒ u = 30