At a Price of $20 Per Unit,140 Units of Goods

At a price of $20 per unit,140 units of goods are demanded and 100 units are supplied.When the price is raised to $30 per unit,100 units are demanded and 140 units are supplied.The price elasticity of supply in this range is:

A) 1.0.
B) 0.834.
C) 0.417.
D) 1.20.
The change in quantity is (140 - 100) /(140 + 100) = 0.167 and the change in price is (30 - 20) /(30 + 20) = 0.20.Thus,elasticity is 0.167/0.20 = 0.835.