1. The quantity of apartments demanded is at the market equilibrium but increases / decreases to when a price ceiling is imposed at $800. 2. The quantity of apartments supplied is at the market equilibrium but increases / decreases to when a price ceiling is imposed at $800. 3. Mth a price ceiling at $800, the quantity of apartments demanded is greater than / less than the quantity of apartments supplied, leading to a surplus / shortage of apartments. 4. The quantity of apartments demanded is at the market equilibrium and when a price ceiling is imposed at $1200. 5. The quantity of apartments supplied is at the market equilibrium and when a price ceiling is imposed at $1200. 6. At the price of $800, the amount of the shortage is units of housing