题目

阅读短文, 按要求回答问题。The face-down generation（一代）If you were born in the 2000s, you are called the oh-ohs. The 21stcentury. That would make you young, creative, connected, world-wide, and no doubt smart. Maybe good-looking, too. Right? But what do other people think about your generation?Some adults worry that you're more interested in the screen in front of you than the world around you. They think of you as the face-down generation because you use your phone so much. They wonder how you will deal with school, friends, and family.Other adults worry that today's youth 如图是A、B两种物质的饱和溶液的溶质的质量分数随温度变化的曲线，现将20g A和40g B分别置于100g水中，加热使其完全溶解，然后再冷却到t℃，下列有关叙述中正确的是 [　　] A．t℃时，A溶液的溶质的质量分数小于B B．t℃时，A溶液的溶质的质量分数等于B C．t℃时，两溶液中均无固体物质析出 D．t℃时，二者的溶解度相等