[{"id": 1, "type": "short_answer", "skill": "area", "question": "Find the area of a rectangle: length=10, width=3", "difficulty": "medium", "explanation": "A=l×w=10×3=30 sq units.", "needs_review": false, "correct_answer": "30"}, {"id": 2, "type": "multiple_choice", "skill": "perimeter", "options": ["40", "30", "26", "13"], "question": "Find the perimeter of a rectangle: length=10, width=3", "difficulty": "medium", "explanation": "P=2(l+w)=2(10+3)=2(13)=26", "needs_review": false, "correct_answer": "26"}, {"id": 3, "type": "short_answer", "skill": "computation", "question": "Calculate: 13 × 6", "difficulty": "medium", "explanation": "Multiply: 13×6=78", "needs_review": false, "correct_answer": "78"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 11 × 10", "difficulty": "medium", "explanation": "Multiply: 11×10=110", "needs_review": false, "correct_answer": "110"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 3 × 9", "difficulty": "medium", "explanation": "Multiply: 3×9=27", "needs_review": false, "correct_answer": "27"}, {"id": 6, "type": "short_answer", "skill": "computation", "question": "Calculate: 8 × 12", "difficulty": "medium", "explanation": "Multiply: 8×12=96", "needs_review": false, "correct_answer": "96"}, {"id": 7, "type": "short_answer", "skill": "computation", "question": "Calculate: 17 × 5", "difficulty": "medium", "explanation": "Multiply: 17×5=85", "needs_review": false, "correct_answer": "85"}, {"id": 8, "type": "short_answer", "skill": "computation", "question": "Calculate: 9 × 7", "difficulty": "medium", "explanation": "Multiply: 9×7=63", "needs_review": false, "correct_answer": "63"}]