Group 1 - The article discusses the tax implications of promotional sales strategies such as "buy one, get one free," indicating that if the sales amount and discount amount are separately stated on the same invoice, VAT can be levied on the discounted sales amount as per the regulations outlined in the National Tax Administration's notice [4][4]. - It clarifies that for corporate income tax purposes, such promotional sales do not qualify as donations and therefore do not need to be treated as sales [4]. - The article emphasizes the need to allocate total sales revenue between different products (e.g., outerwear and scarves) based on their fair values when recognizing income [4]. Group 2 - The article provides a step-by-step guide on how to use the electronic tax bureau app for invoice queries, detailing the process from logging in to checking invoice details [12][13]. - It explains the two query modes available in the invoice query section: "full" and "last 24 hours," and how to input the necessary information to retrieve invoice data [13]. - The article outlines the options available for downloading invoices, including viewing, QR code download, PDF, OFD, and XML formats [14].