[{"id": 1, "type": "short_answer", "skill": "computation", "question": "Calculate: 79 + 45", "difficulty": "medium", "explanation": "Add systematically.", "needs_review": false, "correct_answer": "124"}, {"id": 2, "type": "multiple_choice", "skill": "properties", "options": ["Identity property", "Commutative property", "Associative property", "Distributive 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: 11 × 13", "difficulty": "medium", "explanation": "Multiply: 11×13=143", "needs_review": false, "correct_answer": "143"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 15 × 8", "difficulty": "medium", "explanation": "Multiply: 15×8=120", "needs_review": false, "correct_answer": "120"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 6 × 20", "difficulty": "medium", "explanation": "Multiply: 6×20=120", "needs_review": false, "correct_answer": "120"}, {"id": 6, "type": "short_answer", "skill": "computation", "question": "Calculate: 8 × 15", "difficulty": "medium", "explanation": "Multiply: 8×15=120", "needs_review": false, "correct_answer": "120"}, {"id": 7, "type": "short_answer", "skill": "computation", "question": "Calculate: 10 × 5", "difficulty": "medium", "explanation": "Multiply: 10×5=50", "needs_review": false, "correct_answer": "50"}, {"id": 8, "type": "short_answer", "skill": "computation", "question": "Calculate: 4 × 2", "difficulty": "medium", "explanation": "Multiply: 4×2=8", "needs_review": false, "correct_answer": "8"}]