Rosa is a retired teacher living in Miami who coaches youth soccer to supplement their normal income. At an hourly wage rate of $25, they are willing to coach 9 hours per week. Upping the wage to $50 per hour, they are willing to coach 17 hours per week. Using the midpoint method, the elasticity of Rosa's labor supply between the wages of $25 and $50 per hour is approximately , which means that Rosa's supply of labor over this wage range is