Animalsseemtohavethesensetoeatwhentheyarehungryandtheyd...
问题详情：Animalsseemtohavethesensetoeatwhentheyarehungryandtheydonoteatmorethantheirbodiesneed.Ithasbeenshownthatratswill,whengivenachoiceoveraperiodoftime,preferwaterwithvitamins(维生素)towaterwithout...