Problem: In the City of Joplin, due to weather devastation and hurricane effects, the cost of parking in the local Square has increased by 20%. This change has not only reduced the number of vehicles that travel to the Square by 5%, but it has also forced the inhabitants of Joplin to use buses. Bus trips have therefore increased to 20%. With respect to the cost of parking in the local Square, determine the elasticity of vehicle traffic. ____