异长自身调节是指心脏每搏输出量取决于心室舒张末期容积。
参考答案:对
English _____in many countries, but Chinese _____their own language.
A.is spoken, speaks
B.speaks, is spoken
C.is spoken , speak
D.is spoken, is spoken
根据《通信管道工程施工及验收规范》,核定塑料管道路由应尽量沿各种交通线,或至少应满足沿线所使用气流法敷设光缆气吹点的位置至交通线的距离不大于(),以便使气吹设备和光缆能够顺利到位。