[{"id": 1, "type": "short_answer", "skill": "area", "question": "Find the area of a rectangle: length=6, width=5", "difficulty": "medium", "explanation": "A=l×w=6×5=30 sq units.", "needs_review": false, "correct_answer": "30"}, {"id": 2, "type": "multiple_choice", "skill": "perimeter", "options": ["22", "11", "24", "30"], "question": "Find the perimeter of a rectangle: length=6, width=5", "difficulty": "medium", "explanation": "P=2(l+w)=2(6+5)=2(11)=22", "needs_review": false, "correct_answer": "22"}, {"id": 3, "type": "short_answer", "skill": "computation", "question": "Calculate: 20 × 10", "difficulty": "medium", "explanation": "Multiply: 20×10=200", "needs_review": false, "correct_answer": "200"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 5 × 12", "difficulty": "medium", "explanation": "Multiply: 5×12=60", "needs_review": false, "correct_answer": "60"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 13 × 5", "difficulty": "medium", "explanation": "Multiply: 13×5=65", "needs_review": false, "correct_answer": "65"}, {"id": 6, "type": "short_answer", "skill": "computation", "question": "Calculate: 11 × 11", "difficulty": "medium", "explanation": "Multiply: 11×11=121", "needs_review": false, "correct_answer": "121"}, {"id": 7, "type": "short_answer", "skill": "computation", "question": "Calculate: 15 × 4", "difficulty": "medium", "explanation": "Multiply: 15×4=60", "needs_review": false, "correct_answer": "60"}, {"id": 8, "type": "short_answer", "skill": "computation", "question": "Calculate: 20 × 17", "difficulty": "medium", "explanation": "Multiply: 20×17=340", "needs_review": false, "correct_answer": "340"}, {"id": 9, "type": "short_answer", "skill": "computation", "question": "Calculate: 12 × 3", "difficulty": "medium", "explanation": "Multiply: 12×3=36", "needs_review": false, "correct_answer": "36"}, {"id": 10, "type": "short_answer", "skill": "computation", "question": "Calculate: 15 × 9", "difficulty": "medium", "explanation": "Multiply: 15×9=135", "needs_review": false, "correct_answer": "135"}, {"id": 11, "type": "short_answer", "skill": "computation", "question": "Calculate: 10 × 5", "difficulty": "medium", "explanation": "Multiply: 10×5=50", "needs_review": false, "correct_answer": "50"}, {"id": 12, "type": "short_answer", "skill": "computation", "question": "Calculate: 12 × 20", "difficulty": "medium", "explanation": "Multiply: 12×20=240", "needs_review": false, "correct_answer": "240"}]