Greg uses the high-low method of estimating costs of ABC Inc. Greg had total costs of $50,000 at its lowest level of activity, when 4,400 units were sold. At its highest level of activity, the sales were 10,000 units and the total costs were $78,154. What is the estimated variable cost per unit? Please round your final answer to 2 decimal places (i.e., round 2.324 to 2.32 and round 2.326 to 2.33)