[{"id": 1, "type": "short_answer", "skill": "computation", "question": "Calculate: 84 + 10", "difficulty": "medium", "explanation": "Add systematically.", "needs_review": false, "correct_answer": "94"}, {"id": 2, "type": "multiple_choice", "skill": "properties", "options": ["Distributive property", "Commutative property", "Associative property", "Identity 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: 8 × 16", "difficulty": "medium", "explanation": "Multiply: 8×16=128", "needs_review": false, "correct_answer": "128"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 6 × 14", "difficulty": "medium", "explanation": "Multiply: 6×14=84", "needs_review": false, "correct_answer": "84"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 4 × 20", "difficulty": "medium", "explanation": "Multiply: 4×20=80", "needs_review": false, "correct_answer": "80"}, {"id": 6, "type": "short_answer", "skill": "computation", "question": "Calculate: 2 × 3", "difficulty": "medium", "explanation": "Multiply: 2×3=6", "needs_review": false, "correct_answer": "6"}, {"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: 15 × 6", "difficulty": "medium", "explanation": "Multiply: 15×6=90", "needs_review": false, "correct_answer": "90"}, {"id": 9, "type": "short_answer", "skill": "computation", "question": "Calculate: 18 × 7", "difficulty": "medium", "explanation": "Multiply: 18×7=126", "needs_review": false, "correct_answer": "126"}, {"id": 10, "type": "short_answer", "skill": "computation", "question": "Calculate: 7 × 14", "difficulty": "medium", "explanation": "Multiply: 7×14=98", "needs_review": false, "correct_answer": "98"}, {"id": 11, "type": "short_answer", "skill": "computation", "question": "Calculate: 19 × 20", "difficulty": "medium", "explanation": "Multiply: 19×20=380", "needs_review": false, "correct_answer": "380"}, {"id": 12, "type": "short_answer", "skill": "computation", "question": "Calculate: 10 × 10", "difficulty": "medium", "explanation": "Multiply: 10×10=100", "needs_review": false, "correct_answer": "100"}]