Short answers, pulled from the story.
German engineers tested a new recoil-operated air-cooled machine gun in 1929 that would eventually become the MG 34. The Reichswehrministerium ordered Rheinmetall and other companies to develop an Einheitsmaschinengewehr concept in 1932.
Total MG 34 production reached over 350,000 units across multiple years between 1939 and 1945. Production peaked at 80,952 units in 1941 before declining to 20,297 units in 1945.
A standard German infantry Gruppe squad consisted of ten men including a non-commissioned officer squad leader and deputy. Three-man machine gun teams operated each weapon with five riflemen providing security while carrying additional ammunition totaling 1,800 rounds specifically allocated for their machine gun.
Norway converted original designs to .30-06 Springfield caliber designated MG34F1 then later to 7.62×51mm NATO as MG34F2 serving Norwegian Home Guard until mid-1990s. Greece maintained operational stocks through 2023 according to Hellenic National Defence General Staff reports.
Service life expectancy reached about 6,000 rounds assuming regulations prohibiting rapid sustained fire beyond 250 rounds were followed. Barrel changes took only 10 to 15 seconds when performed by well-trained crews using protective asbestos mitts.