— What do you do on the weekend?
— I often play _______ chess and sometimes I play ______ guitar.
A:the; the
B:the; /
C:/; /
D:/; the
如下图所示,V1和V2是完全相同的两个电压表,都有3V和15V两个量程,闭合开关后,发现两个电压表偏转的角度相同,则R1和R2两端的电压比为
下列长江的支流中,最东边的一条是 ( ).