-5的相反数是( )
A:-15
B:15
C:-5
D:5
— . Ours is much stronger than theirs.
甲、乙、丙三种固体的溶解度曲线如图。将t1℃时甲、丙饱和溶液的试管(均有少量未溶解的固体)放进盛有热水(t2℃)的烧杯里。下列有关说法正确的是