A solution is prepared by adding 50.0 g of NaNO3 to 50.0 g of H2O. It is stirred at 70°C until it becomes clear. Then, it is cooled down to 40°C where it is observed to be still clear. Select the statement that correctly describes the solution at 40°C. (Solubility of NaNO3 at 40°C is 102 g NaNO3 per 100 g H2O.)