下钻过程中，吊卡距转盘（）左右时，内钳工要一手扶吊环，一手拿保险销。
A.0.5m
B.1m
C.1.5m
D.2m
参考答案：C
On April 12, 1961, _______ 27-year-old Yuri Gagarin (尤里·加加林) became the first human to go
into _______ space. [ ]
A. the; 不填
B. the; the
C. a; 不填
D. a; the
化学键
