6th Question: IV. in the Requirements.
When the price of a good is fixed below the equilibrium price level, a price ceiling is said to exist in the market for the good in question. Price alone will be an inadequate mechanism for allocating the available supply of the good among potential buyers, and some other allocative mechanism such as first come-first served, reliance on supplier's preferences, or rationing, may be employed. Black markets may develop when price ceilings are in place. Black markets can exist whenever someone is willing to pay in excess of the set price for a good under a price ceiling regime.
Price ceilings, thus, have the effect of limiting supply because goods providers no longer have the incentive to produce more goods when they are unable to charge more for the goods. Because producers will not have the incentive to bring more products to market, supply shortages will develop. Demand in such situations typically will exceed supply, which in turn will create the conditions conducive to the development of black markets.
Rent control is an example of a price ceiling. Rent control tends to deter the development of new housing units; thereby causing the price of non-rent control rental housing to increase in price. Some politicians favor price ceilings because it curries favor for them among constituents (who presumably are not economists).
7th Question: V. in the Requirements.
The contention that inflation (on average) has no cost because it makes people neither richer nor poorer is false. There are narrow circumstances wherein inflation may not make some people either richer or poorer in a monetary sense because the results of inflation among people who are unable to save money in the first place will simply consume less. In an absolute sense, however, these people will become poorer because their quality if life will deteriorate.
Inflation introduces artificial costs into the economy. I...