71.  The medice conditions are improved, The developing counties can deal with many diffient illnesses, So that the developing countries's life expectancy became higher.

72.  The devoleping countries have a low industrical level in 1960 so that there is a higher infant mortaility and a lower life expectancy.

73.  At first, with the productivity force developing, people have higher living levels.

74.  But the infant mortaility in developing countries was very high.

75.  Depending on the governments and science technique , life expency will grow higher and infant mortaility will turn lower in future .

76.  In my opinion, for one thing, China now is becoming more and more prosperous since he persued his open-door policy, as a result people's living standar is higher than before .

77.  In one word, the better living-condition , the higher life expectancy and lower baby's infant mortality.

78.  The life exectancy is low but the infant mortality is very high.

79.  At that terrible situation, the life expectancy is low and the infant mortality is high.

80.  The people's living level was not high.