阅读下面短文，在空白处填入适当的内容（1个单词）或括号内单词的正确形式。So far, China's BeiDou Navigation Satellite System has been widely used in agriculture. It is helping 【1】(farmer) apply fertilizers (化肥) and pesticides more 【2】(precise). An intelligent fertilizer-pesticide distributor, 【3】 (assist) by the BeiDou Navigation Satellite System and big data technology, has been working in the wheat field in Hancun village in Jiangdu county, east China’s Jiangsu Province. Through the remote network technology service platform, the machine can