[{"id": 1, "type": "short_answer", "skill": "area", "question": "Find the area of a rectangle: length=11, width=5", "difficulty": "medium", "explanation": "A=l×w=11×5=55 sq units.", "needs_review": false, "correct_answer": "55"}, {"id": 2, "type": "multiple_choice", "skill": "perimeter", "options": ["32", "55", "44", "16"], "question": "Find the perimeter of a rectangle: length=11, width=5", "difficulty": "medium", "explanation": "P=2(l+w)=2(11+5)=2(16)=32", "needs_review": false, "correct_answer": "32"}, {"id": 3, "type": "short_answer", "skill": "computation", "question": "Calculate: 17 × 13", "difficulty": "medium", "explanation": "Multiply: 17×13=221", "needs_review": false, "correct_answer": "221"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 15 × 9", "difficulty": "medium", "explanation": "Multiply: 15×9=135", "needs_review": false, "correct_answer": "135"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 18 × 7", "difficulty": "medium", "explanation": "Multiply: 18×7=126", "needs_review": false, "correct_answer": "126"}]