Analisis kestabilan lereng menggunakan Metode RMR (Rock Mass Rating) untuk menentukan faktor keamanan lereng di Kawasan Tambang Tuf Desa Candirejo, Kecamatan Semin, Kabupaten Gunungkidul, Provinsi Daerah Istimewa Yogyakarta = Stability analysis of slopes using the RMR (Rock Mass Rating) Method to determine slope safety factors in the tuff quarry area of Candirejo Village, Semin District, Gunungkidul Regency, Special Region of Yogyakarta Province