Context: On 13 December 1904, Hungarian Sándor Just and Croatian Franjo Hanaman were granted a Hungarian patent (No. 34541) for a tungsten filament lamp that lasted longer and gave brighter light than the carbon filament. Tungsten filament lamps were first marketed by the Hungarian company Tungsram in 1904. This type is often called Tungsram-bulbs in many European countries. Filling a bulb with an inert gas such as argon or nitrogen retards the evaporation of the tungsten filament compared to operating it in a vacuum. This allows for greater temperatures and therefore greater efficacy with less reduction in filament life.

Question: Which inventors patented the tungsten filament lamp?
Answer: Hungarian Sándor Just and Croatian Franjo Hanaman

Question: When did Just and Hanaman receive their patent for the tungsten filament lamp?
Answer: 13 December 1904

Question: Which company first marketed the tungsten filament lamp?
Answer: Tungsram

Question: What type of gas fills a tungsten filament bulb?
Answer: argon or nitrogen

Question: What is a common alternate name for the tungsten filament bulb in Europe?
Answer: Tungsram-bulbs

Question: Who was not granted a patent fr the tungsten filament lamp?
Answer: Unanswerable

Question: Who was granted patent No. 34540?
Answer: Unanswerable

Question: Who receive their patent in 1905?
Answer: Unanswerable

Question: What type of gas does not fill a tungsten filament bulb?
Answer: Unanswerable

Question: What is not a common alternate name for the tungsten filament bulb in Europe.
Answer: Unanswerable