\(20\) g of gold (Au) and \(20\) g of silver (Ag) are mixed to form a single phase solid solution (assume ideal mixing). The atomic weight of Au is \(197\) g/mol and the atomic weight of Ag is \(108\) g/mol. The universal gas constant \(R = 8.314\ \text{J/mol-K}\). Find the total entropy of mixing (rounded off to two decimal places), in J/K.