单项选择题
A.50~100倍B.500~1000倍C.1000~2000倍D.100~200倍
配制营养液时,优质用水的EC值通常为()A.〈0.2ms/cmB.≥0.5ms/cmC.≥0.3ms/cmD....
单项选择题配制营养液时,优质用水的EC值通常为()
A.〈0.2ms/cmB.≥0.5ms/cmC.≥0.3ms/cmD.〈0.1ms/cm
固体基质适宜的容重为()A.1~2g/cm3B.3~5g/cm3C.0.1~0.8g/cm3D.1~8g/cm...
单项选择题固体基质适宜的容重为()
A.1~2g/cm3B.3~5g/cm3C.0.1~0.8g/cm3D.1~8g/cm3
番茄的光饱和点为()A.5000lxB.20000lxC.70000lxD.50000lx
单项选择题番茄的光饱和点为()
A.5000lxB.20000lxC.70000lxD.50000lx