1. historia   algebra   botany   history   astronomy   Hint Half-n-half Clue   2. zoología   geography   zoology   history   biology   Half-n-half Clue   3. psicología   zoology   algebra   psychology   biology   Half-n-half Clue   4. química   physics   geology   geography   chemistry   Half-n-half Clue   5. geografía   astronomy   history   physics   geography   Half-n-half Clue   6. trigonometría   zoology   philosophy   trigonometry   botany   Half-n-half Clue   7. cálculo   calculus   geometry   philosophy   botany   Half-n-half Clue