B

Most children don't enjoy doing housework. They like playing computer games rather than cleaning the rooms. But in Australia, Jim and Robert's mother, Mrs. Black, has good and proper methods to get their children to do housework. Here is an example. "Mum, have you worked out next week's housework? Let Jim and me choose the cards I can't wait. It's fun!" When Robert shouted out, his mother had already put all the cards on their big table. On the cards, there are some words like these, "sweep the floor, clean your bedroom, help mum cook, wash vegetables, make beds, feed the fish, cut the wood, clean the bathroom" and many others, Jim and Robert chose two cards for each day from Monday to Friday. Then they would hang them on the week day task board. Jim likes to clean the bathroom, so he picked up the card "clean the bathroom". Robert loves to make the bed so he picked up his favorite card. Jim again picked up "wash vegetables" and Robert chose "feed the fish". Soon the two boys were happy to take away all the cards to help the children do housework, their mother thought hard and came up with this idea. Of course, the parents did the housework on the weekends and left Jim and Robert two days free.

                                                                    Ryan

如图是甲、乙两种固体的溶解度曲线．下列说法中不正确的是（）