问题
选择题
-Tom hasn't paid for the school things, has he?
-__________. His mother will pay for them. [ ]
A. Yes, he has
B. No, he hasn't
C. Yes, he did
D. No, he didn't
答案
答案：B
搜题请搜索小程序“爱下问搜题”
-Tom hasn't paid for the school things, has he?
-__________. His mother will pay for them. [ ]
A. Yes, he has
B. No, he hasn't
C. Yes, he did
D. No, he didn't
答案：B
时，加速度又变为a，直至速度为
时，加速度再变为－a，直到速度变为－
…，其v－t图象如图1所示，则下列说法正确的是 ( )