THE EFFECTIVENESS OF VIDEO-ASSISTED PROBLEM-BASED LEARNING MODEL ON STUDENTS’ SCIENCE LITERACY SKILLS OF VIBRATION AND WAVE MATERIAL IN SMP NEGERI 27 MEDAN. universe [Internet]. 17 September 2024 [dikutip 14 Agustus 2026];5(1):134-49. Tersedia pada: http://universe.ppj.unp.ac.id/index.php/universe/article/view/925