[{"id": 1, "type": "short_answer", "skill": "area", "question": "Find the area of a rectangle: length=5, width=6", "difficulty": "medium", "explanation": "A=l×w=5×6=30 sq units.", "needs_review": false, "correct_answer": "30"}, {"id": 2, "type": "multiple_choice", "skill": "perimeter", "options": ["11", "30", "22", "20"], "question": "Find the perimeter of a rectangle: length=5, width=6", "difficulty": "medium", "explanation": "P=2(l+w)=2(5+6)=2(11)=22", "needs_review": false, "correct_answer": "22"}, {"id": 3, "type": "short_answer", "skill": "computation", "question": "Calculate: 19 × 15", "difficulty": "medium", "explanation": "Multiply: 19×15=285", "needs_review": false, "correct_answer": "285"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 5 × 5", "difficulty": "medium", "explanation": "Multiply: 5×5=25", "needs_review": false, "correct_answer": "25"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 13 × 9", "difficulty": "medium", "explanation": "Multiply: 13×9=117", "needs_review": false, "correct_answer": "117"}]