单项选择题Which of the following belongs to facilitated diffusion? A、inflow of O2 B、outflow of CO2 C、inflow of Na+ in erythrocyte D、releasiong of ACh
单项选择题现有的污水处理工艺可以高效去除环境中的持久性有机污染物。（ ） A、正确 B、错误
