Suppose a linear demand curve is given by the formulaQ = 400 - 10 P

The price elasticity of demand at P=30 is___. The price elasticity of demand at Q=400 is.

At Q =___, the price elasticity of demand is -1.

If the price increases from 22 to 23, the total revenue of the seller___.

Instruction: If the total revenue remains the same write 0. If the total revenue decreases, write 1. If the total revenue increases, write 2.