Perbandingan Kumur Magnesium Sulfat dengan Kumur Benzydamine Hydrochloride Dalam Mengurangi Kejadian Nyeri Tenggorok Setelah Pemasangan Laryngeal Mask Airway = Comparison of Magnesium Sulfate Gargle with Benzydamine Hydrochloride Gargle in Reducing Postoperative Sore Throat After Insertion of a Laryngeal Mask Airway