用科学记数法表示﹣0.0000064记为[ ]
A.﹣64×10﹣7
B.﹣0.64×10﹣4
C.﹣6.4×10﹣6
D.﹣640?10﹣8
答案:C
As a child, Jack studied in a village school,_______ is named after his grandfather.
A.which
B.where
C.what
D.that
为避免早产儿发生呼吸窘迫综合征,可在分娩前给予孕妇______静脉注射。