来自MSN5 个月
We all know the symbol of the broken heart, but where did it come from? Art history has ...the heart is most often represented in European art from the Middle Ages onwards in a more anatomically correct manner than the symbol we have come to know and love. Many pre-modern hearts feature ...
Symbol equations are a quick way of representing chemical reactions. They show us what atoms are involved and how they are bonded together. Symbol equations always take the form, reactants → ...
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