Answer:
b. A normal good and income - elastic
Explanation:
Solution
Using the midpoint method
change in Qd     ÷      change in income
old Qd + New Qd      old income + New income Â
     2                     2
change in Qd  = 4 - 3 = 1
change in income = 109,500 - 102,750 = 67,500
going by the formula
1/3.5  ÷ 67,500/106,125
1/3.5 x 106,125/ 67,500
= 0.45
The income elasticity of demand is 0.45 meaning it is inelastic because it is less than one.
And the good is a normal good because the demand for it increases as income increases. Â