8 Data on price of Y, quantity demand for X when income is 100, and quantity demand for X when income is 200 are given in the following table. The price of X is fixed at $7. Py QDx (Income $100) QDx (Income $200) 0 121.5 196.5 1 120.2 195.2 IN 118.9 193.9 117.6 192.6 1 16.3 191.3 115 190 113.7 188.7 112.4 187.4 111.1 186.1 109.8 184.8 10 108.5 183.5 a Calculate income elasticity of demand for X using the midpoint method when income increases from $100 to $200 and when price of Y is fixed at $9. Explain your answer. (5 marks) b. Calculate cross price elasticity of demand for X when price of Y decreases from $9 to $8 and when income is $100. Explain your