位于波罗的海沿岸的重要城市是( )
A.莫斯科
B.伊尔库茨克
C.符拉迪沃斯托克
D.圣彼得堡
位于波罗的海沿岸的重要城市是圣彼得堡,该城市是俄罗斯的第二大城市.
故选:D.
A: Your bicycle looks very nice. When did you buy it?
B: Oh, I ______ it for three months. It's a birthday present from my uncle. [ ]
A. bought
B. have bought
C. have received
D. have had
对于一个部位的扫描,动态单层扫描较非螺旋扫描节约时间()
A.约二分之一
B.约三分之一
C.约四分之一
D.约五分之一
E.约三分之二