Economists have estimated the following transportation elastics .For each pair,explian possible reason why the elasticities differ.

a.Elasticity of demand for buses is 0.23 during peak hour and 0.42 during off-peak hours.

b.Elasticity of demand of buses is 0.7 in the short run and 1.5 in the long run.

c.Elasticity of demand for toll road 4.7 for low-income commuters and 0.63 high-income commuters.