[{"id": 1, "type": "short_answer", "skill": "area", "question": "Find the area of a rectangle: length=10, width=5", "difficulty": "medium", "explanation": "A=l×w=10×5=50 sq units.", "needs_review": false, "correct_answer": "50"}, {"id": 2, "type": "multiple_choice", "skill": "perimeter", "options": ["30", "50", "15", "40"], "question": "Find the perimeter of a rectangle: length=10, width=5", "difficulty": "medium", "explanation": "P=2(l+w)=2(10+5)=2(15)=30", "needs_review": false, "correct_answer": "30"}, {"id": 3, "type": "short_answer", "skill": "computation", "question": "Calculate: 12 × 8", "difficulty": "medium", "explanation": "Multiply: 12×8=96", "needs_review": false, "correct_answer": "96"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 14 × 14", "difficulty": "medium", "explanation": "Multiply: 14×14=196", "needs_review": false, "correct_answer": "196"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 10 × 12", "difficulty": "medium", "explanation": "Multiply: 10×12=120", "needs_review": false, "correct_answer": "120"}]