阅读短文，选择填空。

    My grandfather is fifty-five years old. He's a taxi driver. He loves his job very much. It is Sunday. Today is his birthday. My father, my mother and I are in his home. My uncle also comes here. He's a tall man. He's a worker. He comes to see my grandfather every Sunday. My grandfather has a good friend. His name is Jim. He's from England. He's a nice cook. He comes to see him, too. My grandfather is very happy today.

改革开放三十年来，我国的社会主义现代化建设取得了举世瞩目的伟大成就，经济、社会快速发展，国家日益繁荣昌盛，真正跨入了民族振兴的时代。从中我们可以悟出（  ）

抚养比是指人口中非劳动年龄人口数与劳动年龄人口数之比。当总抚养比≤50%时称为人口红利期。下图是我国沿海某省2000～2010年抚养比变化。

除去乙酸乙酯中乙酸杂质，下列方法可行的是(　　)

下列关于元素第一电离能的说法不正确的是（　　）