how to compute the elasticities for independent variable

Q = Quantity demand for 3-pack units

P (in cents) =Price of the product = 500 cents per 3-pack unit

PX (in cents) = Price of leading competitorâ€™s product = 600 cents per 3-pack unit

I (in dollars) = Per capita income of the standard metropolitan statistical area (SMSA) in which the supermarkets are located = $5,500

A (in dollars) Monthly advertising expenditures = $10,000

M=Number of microwave ovens sold in the SMSA in which the supermarkets are located = 5,000