Suppose jane eats cheese sandwiches, using precisely two slices of bread and two slices of cheese to make one sandwich. (a) by finding the demand function for cheese, derive formulae for the elasticity of demand for cheese, the cross-price elasticity of demand for cheese with respect to the price of bread, and the income elasticity of demand for cheese. (b) what would be the values of these elasticities if the price of a slice of bread is equal to the price of a slice of cheese? verify that the sum of these three elasticities is zero. (c) what would be the values of the elasticities if the price of a slice of cheese was twice the price of a slice of bread?