Elasticity of Demand: AP Microeconomics online Test

With a change in the price, if the quantity of a commodity demanded remains the same, the coefficient of price elasticity of demand is:
Equal to 1
Less than 1
Greater than 1
Zero
Infinite
/
I only
III only
I and IV
III and IV
I and III
If the demand curve becomes parallel to the quantity axis, the price elasticity of demand is:
Equal to 1
Less than 1
Greater than 1
Zero
Infinite
The method to measure Cross Elasticity of Demand is:
Percentage change in the Price of Commodity X divided by Percentage change in Quantity demanded of Commodity Y
Percentage change in the Quantity of Commodity demanded divided by Percentage change in its Price
Percentage change in the quantity demanded of commodity X divided by the percentage change in quantity demanded of commodity Y
Percentage change in the quantity demanded of commodity X divided by percentage change in price of commodity Y
Percentage change in the price of commodity Y divided by percentage change in quantity demanded of commodity X
If a Percentage change in Quantity Demanded is greater than the Percentage change in Price, the Elasticity of Demand is:
Perfectly Elastic
Unitary Elastic
Elastic
Inelastic
Perfectly Inelastic
If the Price of a commodity changes from $16 to $12, the Quantity Demanded changes from 30 to 60 units, the Elasticity of Demand is:
0.5
4
8
2.6
-4
Negative Cross-Elasticity of Commodity X with respect to the Price of a related Commodity Y implies that:
Commodity X is expensive than Commodity Y
Commodity Y is expensive than Commodity X
Commodity X and Commodity Y are substitutes of each other.
Both Commodities X and Y are complementary to each other.
Both Commodities X and Y have the same price.
/
Only I
Only II
Only III
I and II
I and III
The Economist associated with the development of the Theory of Elasticity of Demand is:
Boulding
Alfred Marshall
Lipsey
Watson
Samuelson
The Arc Elasticity of Demand for a commodity, of which the Quantities demanded are Q1 and Q2 for the prices P1 and P2, is:
Q1+Q2 x P2-P1 P1+P2 Q2-Q1
Q1+Q2 x Q2-Q1 P1+P2 P2-P1
Q1-Q2 x P1+P2 Q1+Q2 P2-P1
Q1-Q2 x P1-P2 Q1+Q2 P2+P1
Q1-Q2 x P2-P1 Q1+Q2 P2+P1