— Who came to school earliest yesterday morning?
— ______. You can ask Linda. She may know.
A:I'm afraid not
B:I think so
C:I've no idea
D:You're welcome
第一部社会主义类型的宪法是指( )
下列有关蛋白质的说法,正确的是( )
如图所示,电源电压是5V并保持不变,开关S闭合后电压表的示数为3V,则( )
已知x=3+1,y=3-1,求下列各式的值
(1)x2+2xy+y2 (2)x2+y2﹣5xy.
读图1青岛地形图,图2青岛某山地植被分布图,