[经] marginal productivity of labour

láo dòng lì de biān jì shēng chǎn lǜ ㄌㄠˊ ㄉㄨㄥˋ ㄌㄧˋ ㄉㄜ˙ ㄅㄧㄢ ㄐㄧˋ ㄕㄥ ㄔㄢˇ lv4