中央银行票据的特点是( )。
A.无风险、期限短、流动性高
B.无风险、期限长、流动性高
C.无风险、期限长、流动性低
D.无风险、期限短、流动性低
参考答案:A
若抛物线y=ax2+bx+c(a≠0)经过原点和第一,二,三象限,则[ ]
A.a>0,b>0,c=0
B.a>0,b<0,c=0
C.a<0,b>0,c=0
D.a<0,b<0,c=0
Although the new road is being used, it has not yet been _______opened.
A.gradually
B.actually
C.officially
D.frequently