Junior High School Students’ Mathematical Representation Skills in Solving Data and Diagram Problems: The Gap Between Verbal, Visual, and Symbolic Representations Alya Lhutfiani, Uut Ulandari, Iftina Nur Aini, Kevi Andinia Putri Ginanta, Reni Wahyuni Jurnal Pendidikan Matematika Vol. 17 No. 2 2026 DOI 10.36709/jpm.v17i2.389