Answer:
Inelastic; 5%; fall; 10%; rise
Explanation:
Price elasticity of demand is always negative for normal goods. This happens because of the law of demand, that demand falls with rise in price.
Price elasticity between 0 and 1 shows inelastic demand.
This means that there is smaller change in demand due to a greater change in price level.
Price elasticity of demand is -0.5.
If the price falls by 10%, demand will increase by 5%.
The revenue will fall, because of greater fall in price.
If the price increases by 20%, demand will fall by 10%.
Revenue will increase because of greater increase in price.