A1.5-1: 一个质点在做圆周运动时,则有( )
A. 切向加速度一定改变,法向加速度也改变
B. 切向加速度可能不变,法向加速度一定改变
C. 切向加速度可能不变,法向加速度不变
D. 切向加速度一定改变,法向加速度不变
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It's on sale this week. It's only $32.56.句中on sale的意思是.
A. 销售
B. 买卖
C. 打折
—much is it?—It's only $50,plus tax.
A. How
B. Which
C. What
下面哪些属于新型的支付方式？
A. WeChat Pay
B. Pay in cash
C. Pay by Alipay
D. Face-scanning payment
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