圆筒、圆锥形重介旋流器的溢流管插入深度在（）mm为宜。
A、400—500
B、600—700
C、500—600
D、320—400
参考答案：D
26. According to the arrangement, the newly-elected president _______a speech to his supporters from 8 to 10 o’clock tomorrow morning .
A．is giving
B．will be giving
C．gives
D．will have given
