The circular slide rule is the industry standard for duct design.It is the simplest, most convenient way to take into account the many variables of ductwork analysis.是什么意思_The circular slide rule is the industry standard for duct design.It is the simplest, most convenient way to take into account the many variables of ductwork analysis.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句