A 0.500 g sample of an unknown substance was titrated with a 0.1 M HCl solution.Another 0.500 g sample of it was titrated with a 0.1 M NaOH solution.The resulting titration curves are illustrated here.Given the following possibilities,what is the sample? 
Definitions:
Express Anger
The act of communicating or displaying feelings of displeasure or hostility, often in response to perceived injustices or frustrations.
Engagement
Engagement is a formal agreement between two people to get married, or the period between the proposal and the wedding.
Future In-Laws
The parents of one's fiancé(e) or the parents of one's child's spouse, who are likely to become part of one's extended family through marriage.
Better Acquainted
The process of getting to know someone or something more thoroughly.
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