 Complete the following phrase:  As Maos health began to decline in 1971 and 1972 and following the death of disgraced Lin Biao, Zhou was elected to the vacant position of First Vice Chairman of the Communist Party by the 10th Central Committee in 1973 and thereby designated as Maos successor the third person to be so designated after Liu Shaoqi and Lin, but still struggled internally against the Gang of Four over leadership of China. His last major public appearance was at the first meeting of the 4th National Peoples Congress on 13 January 1975, where he presented the government work report. He then fell out of the public eye for medical treatment and died one year later. The massive public outpouring of grief which his death provoked in Beijing turned to anger at the Gang of Four, leading to the 1976 