The demand curve for 48" Sony flat screen televisions is likely to move to the right when consumer incomes increase.

The demand curve for 48" Sony flat screen televisions is likely to move to the right when the price of 48" Vizio flat screen televisions decreases.

The demand curve for 48" Sony flat screen televisions is likely to move to the right when the price of (all brands of) BluRay players decreases.

A supply curve shows a stable, long-run relationship, since little but the price of a good will affect the quantity of it that producers are willing to sell.

If the government bans steel imports from Japan, this decreases the "quantity of steel demanded" and bought, but not the "demand" for steel.

If demand increases and supply decreases, both quantity and price will decrease.

Suppose that the population increases and, as a result, both the price and quantity of orange juice purchased increases. This shows that demand can sometimes be upward sloping.