Demand of a product is usually very sensitive to economic variables, such as the prices and consumer income. This responsiveness of demand is elasticity. Compute elasticity in the below scenarios:

a. Three days ago, the price of envelopes was $7 a box, and Julie was willing to buy 80 boxes. Today, the price has gone up to $7.75 a box, and Julie is now willing to buy 18 boxes. Is Julie's demand for envelopes elastic or inelastic? What is Julie's elasticity of demand?

b. If Neil's elasticity of demand for hot dogs is constantly 0.9, and he buys 4 hot dogs when the price is $1.50 per hot dog, how many will he buy when the price is $1.00 per hot dog?

4) Explain the different types of Costs in a tabular format & with a well-labelled diagram