What is the size of the workbook?
International standard format includes folio, 16 karats, 32 karats, 64 karats. The workbook is generally 16 karat, that is, A4 (16k) 297mm×210mm. There are also A5 (32k) 210mm × 148mm, A6 (64k) 144mm × 105mm, A2 (2k) 420mm × 594mm, etc.