A municipal bus service faces a constant price elasticity of demand of -0.4 for its transit passes. If the transport authority increases the price of a transit pass by 20%, what is the resulting percentage change in total consumer expenditure on these passes?
A decrease of 8.0%8.0\%8.0%
An increase of 10.4%10.4\%10.4%
An increase of 12.0%12.0\%12.0%
An increase of 20.0%20.0\%20.0%
