When the price of oranges is $5 per lb, the quantity demanded is 100 lbs per week. When the price rises to $20 per lb, the quantity demanded falls to 99 lbs per week. Calculate the price elasticity of demand for oranges, and say whether it is elastic, inelastic, or unit elastic.
When the price of apples is $6 per lb, the quantity demanded is 20 lbs per month. When the price falls to $5 per lb, the quantity demanded increases to 90 lbs per month. Calculate the price elasticity of demand for oranges, and say whether it is elastic, inelastic, or unit elastic.