I need help answering the below question :

3. The demand schedule for wax candles is as shown below. What is the price elasticity of demand between $3 and $4? Assume the manager has been charging $3.00. Make the case for keeping that price or changing the price to $4.00. If you choose to change, demonstrate the businessman's unfailing proof that the change is appropriate. Px Qx $5.00 600 4.00 700 3.00 800 2.00 900 1.00 1,000