1. 生物学   geography   algebra   history   biology   Hint Half-n-half Clue   2. 化学   biology   chemistry   astronomy   physics   Half-n-half Clue   3. 地質学.   physics   geology   astronomy   psychology   Half-n-half Clue   4. 心理学   psychology   geology   astronomy   physics   Half-n-half Clue   5. 歴史   zoology   history   geology   physics   Half-n-half Clue   6. 地理学   geography   psychology   geometry   history   Half-n-half Clue   7. 植物学   botany   psychology   geology   trigonometry   Half-n-half Clue