[{"id": 1, "type": "short_answer", "skill": "computation", "question": "Calculate: 52 + 15", "difficulty": "medium", "explanation": "Add systematically.", "needs_review": false, "correct_answer": "67"}, {"id": 2, "type": "multiple_choice", "skill": "properties", "options": ["Commutative property", "Identity property", "Distributive property", "Associative property"], "question": "Which property states a+0=a?", "difficulty": "easy", "explanation": "The identity property of addition states that adding 0 to any number gives that number.", "needs_review": false, "correct_answer": "Identity property"}, {"id": 3, "type": "short_answer", "skill": "computation", "question": "Calculate: 5 × 3", "difficulty": "medium", "explanation": "Multiply: 5×3=15", "needs_review": false, "correct_answer": "15"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 8 × 18", "difficulty": "medium", "explanation": "Multiply: 8×18=144", "needs_review": false, "correct_answer": "144"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 14 × 11", "difficulty": "medium", "explanation": "Multiply: 14×11=154", "needs_review": false, "correct_answer": "154"}, {"id": 6, "type": "short_answer", "skill": "computation", "question": "Calculate: 11 × 7", "difficulty": "medium", "explanation": "Multiply: 11×7=77", "needs_review": false, "correct_answer": "77"}, {"id": 7, "type": "short_answer", "skill": "computation", "question": "Calculate: 8 × 3", "difficulty": "medium", "explanation": "Multiply: 8×3=24", "needs_review": false, "correct_answer": "24"}, {"id": 8, "type": "short_answer", "skill": "computation", "question": "Calculate: 6 × 7", "difficulty": "medium", "explanation": "Multiply: 6×7=42", "needs_review": false, "correct_answer": "42"}, {"id": 9, "type": "short_answer", "skill": "computation", "question": "Calculate: 3 × 7", "difficulty": "medium", "explanation": "Multiply: 3×7=21", "needs_review": false, "correct_answer": "21"}, {"id": 10, "type": "short_answer", "skill": "computation", "question": "Calculate: 11 × 4", "difficulty": "medium", "explanation": "Multiply: 11×4=44", "needs_review": false, "correct_answer": "44"}, {"id": 11, "type": "short_answer", "skill": "computation", "question": "Calculate: 13 × 18", "difficulty": "medium", "explanation": "Multiply: 13×18=234", "needs_review": false, "correct_answer": "234"}, {"id": 12, "type": "short_answer", "skill": "computation", "question": "Calculate: 19 × 11", "difficulty": "medium", "explanation": "Multiply: 19×11=209", "needs_review": false, "correct_answer": "209"}]