如图标志的含义是什么()
A.禁止直行和向右转弯
B.准许直行和向左转弯
C.禁止直行和向左转弯
D.准许直行和向右转弯
参考答案:C
下列是几种粒子的结构示意图,其中表示阳离子的是( )
A.
B.
C.
D.
A truck departed from Newton at 11:53 a.m. and arrived in Far City, 240 miles away, at 4:41 p.m. on the same day. What was the approximate average speed of the truck on this trip