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美国波拉型相机1977年销售量达七百万架,自1973年以来累计共达三千万架。每年胶片销售量达1.75亿包。美国在1977年销售的一步成象照相机中,国内市场约占40％,
The United States Bola type camera sales in 1977 reached seven million, a total of up to 30 million since 1973. Annual film sales of 175 million packets. In the one-step imaging camera sold by the United States in 1977, the domestic market accounted for about 40%