— ________. I am studying for the model test next week.
A:I'm afraid not.
B:I agree
C:I don't think so
x
0
1
3
4
y
2.2
4.3
4.8
6.7
从散点图分析,y与x线性相关,且 y^ =0.95x+a,则a=____.
有学者认为:“新航路开辟以后,欧洲的商人和殖民者在欧洲、亚洲、非洲、美洲之间建立了直接的商业联系。”这表明( )
如果实数x,y满足:x-y+1≤0x+y-2≤0x+1≥0,则目标函数z=4x+y的最大值为 ( )