A:一个
B:二个
C:三个
D:四个
关于速度和加速度的关系,下列说法中正确的是( )
Today is Monday. Linda is at school. She has Chinese,English and PE in the morning. She doesn't have Music today. She has Maths and Art in the afternoon. She has Music on Fridays.
下列物质中,属于纯净物的是( )
①实现国共合作
②提出新三民主义
③颁布《临时约法》