题目

阅读理解 What would you do if you had invited friends to your house and they askedyou for directions? Well, you could draw a map! And, if you did, you mostlikely would include your street and theirs, as well as the landmarks betweenthe two. Using these places on the map as markers, your friends can then planthe best route to take. Generally speaking, a map is an illustration of the earth's surface, anda person who draws maps is called a cartographer. But how are maps made? Inprehistoric times, hunters would sometimes draw their hunting territories oncave walls. In the millennia that follow16．如图表示的是KNO3和NaNO3的溶解度曲线．下列说法正确的是（　　）A．T2℃时，KNO3溶液的溶质质量分数等于NaNO3溶液的溶质质量分数B．T1℃时，将等质量的KNO3和NaNO3固体配成饱和溶液，所需水较多的是NaNO3C．T1℃时，往180gNaNO3饱和溶液中加入620g水可配成质量分数为10%的NaNO3溶液D．分别将T2℃时，KNO3和NaNO3的饱和溶液降温至T1℃，析出晶体较多的是KNO3溶液