[{"id": 1, "type": "short_answer", "skill": "computation", "question": "Calculate: 93 + 93", "difficulty": "medium", "explanation": "Add systematically.", "needs_review": false, "correct_answer": "186"}, {"id": 2, "type": "multiple_choice", "skill": "properties", "options": ["Commutative property", "Distributive property", "Identity 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: 16 × 15", "difficulty": "medium", "explanation": "Multiply: 16×15=240", "needs_review": false, "correct_answer": "240"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 16 × 4", "difficulty": "medium", "explanation": "Multiply: 16×4=64", "needs_review": false, "correct_answer": "64"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 4 × 13", "difficulty": "medium", "explanation": "Multiply: 4×13=52", "needs_review": false, "correct_answer": "52"}, {"id": 6, "type": "short_answer", "skill": "computation", "question": "Calculate: 8 × 19", "difficulty": "medium", "explanation": "Multiply: 8×19=152", "needs_review": false, "correct_answer": "152"}, {"id": 7, "type": "short_answer", "skill": "computation", "question": "Calculate: 2 × 11", "difficulty": "medium", "explanation": "Multiply: 2×11=22", "needs_review": false, "correct_answer": "22"}, {"id": 8, "type": "short_answer", "skill": "computation", "question": "Calculate: 12 × 12", "difficulty": "medium", "explanation": "Multiply: 12×12=144", "needs_review": false, "correct_answer": "144"}]