Вставить вместо точек предлоги the guarantee period which the company offered … their com- puters was 12 months … the date …putting them … operation and 15 months … the date … delivery. the buyer found it rather short and wanted it to be extended … two and four months respectively. but the company agreed to extend it only … 13 and 17 months.as the seller was responsible … the defects which were found … the equipment, they had to correct them … their expense.