Beth is a retired teacher who lives in Miami and teaches tennis lessons for extra cash. At a wage of $30 per hour, she is willing to teach 3 hours per week. At $50 per hour, she is willing to teach 7 hours per week.

Using the midpoint method, the elasticity of Beth's labor supply between the wages of $30 and $50 per hour is approximately_______ , which means that Beth's supply of labor over this wage range is______ .