Per amount of ?

Their cellphone-systems are designed mostly for indidual usability,
but performance per amount of battery life is important as well.

請問 per amount of 的意思?
請解釋詞性,分析句子
及解釋per amount of三個字單獨拆開和合起來的意思.
更新: 請問per是什麼詞?
請問amount是什麼詞?
請問of是什麼詞?
請問 per amount of 是片語?詞?還是...?
3 個解答 3