Group 1 - The article discusses tax exemption policies for specific agricultural products, including drip irrigation belts and pipes, as well as organic fertilizers, aimed at supporting the agricultural sector [5][12][19]. - Tax exemption for drip irrigation products has been in effect since July 1, 2007, allowing eligible taxpayers to sell these products without VAT [6][11]. - Organic fertilizers are exempt from VAT starting from June 1, 2008, covering various types of organic fertilizers, including organic, organic-inorganic mixed fertilizers, and biological organic fertilizers [15][17]. Group 2 - Taxpayers selling exempt drip irrigation products must issue ordinary invoices and cannot issue special VAT invoices [7]. - For organic fertilizers, similar invoicing rules apply, requiring ordinary invoices for sales [15]. - The article outlines the necessary documentation and procedures for taxpayers to apply for these tax exemptions, including the need to retain relevant proof for verification [9][16]. Group 3 - The article also highlights other tax exemption policies, such as the exemption of consumption tax for ethanol gasoline produced from purchased taxed gasoline, effective since January 1, 2009 [20]. - Another policy mentioned is the exemption of consumption tax for biodiesel produced from waste animal and plant oils, which has been in effect since January 1, 2009, provided certain conditions are met [23].