x=-12时,y=4×(-12)2=4×14=1.
故答案为:1.
-Mom,I’m afraid I’ve got flu.
-________,darling.You’ll be better soon.[ ]
A.Don’t mention it
B.Take it easy
C.Take your time
D.Good luck
生物圈的厚度大约是( )
A.10千米左右
B.5千米左右
C.15千米左右
D.20千米左右