There are three people in Yang Yang's family. They like different kinds of food. Yang Yang likes rice a lot. But she doesn't like chicken at all. Her father is from Shanxi. He doesn't like rice at all. He likes chicken and bread very much. Her mother is from Dalian. She doesn't like rice or bread at all. But she likes fish and vegetables a lot. They love each other and help each other.

下列哪一事件促进了明朝与亚非国家的经济文化交流（    ）

将抛物线y=3x²向左平移2个单位，再向下平移1个单位，所得抛物线为(　　)

黄河哺育了灿烂的中华文明。但是黄河身体上也存在“病症”。读下图，完成下列小题。