题干
Mary is my good friend. She's good-looking but she's quiet.
A：a bit of
B：a lot of
C：a little bit
D：a few
答案(点此获取答案解析）
C
Mary is my good friend. She's good-looking but she's quiet.
A：a bit of
B：a lot of
C：a little bit
D：a few
，熄火后的运动方程为
，则从熄火到火箭速度为0时所需时间
=
