题目

阅读下面短文，从短文后各题所给的A 、B 、C 和D 四个选项中，选出可以填入空白处的最佳选项。Rebecca, who I met at a business conferencein Las Vegas, is one of the1peopleI have ever known. So sharp in mind was she that she made a deep impression on me.Even if you were around her for an entire day, you probably wouldn't notice her2. She was born with severe dyslexia — aslight disorder of the brain that causes difficulty in reading and spelling.3her learning disability, she hadto be in4educationclasses for most of her elementary and middle school years. Despi在一定温度和压强下，将一支容积为15mL的试管充满NO2，后倒置于一个盛水槽中，当试管液面上升至一定高度不变时，在相同条件下再通入O2，若要试管内的液面仍保持在原高度，则通入O2的体积是 [　　] A．3.75mLB．7.5mL C．8.75mLD．10.5mL