It actually varies. It could be a 20mm, 30mm all the way up to 210mm ( most modern tanks use 120mm cannon). It can also have double barreled auto cannon. Basically, current tanks can have anything that is mounted that isn't small arms(excluding LMGs, MMGs, HMGs, rocket launchers, grenade launchers, bazookas, and GPMGs ) it cannot hold railguns ( experimental stage) and it can hold nukes.
Tanks and artillery
Air Force weapons? Or Army weapons? Or Naval Weapons? Or Types of Artillery? Or Types of Small Arms (rifles, pistols, etc.)? Or Tanks? Or Warships?
AK47s and tanks.
Air, land and sea were the types of battles fought in World War 2. They used ships, subs, boats, tanks, large weapons and infantry weapons, fighter planes and bomber planes.
tanks
There were many different types of machinery and weapons used during the war. Rifles, torpedo's, gas and machine guns were all weapons of choice. Tanks, Zeppelins and planes were all used as well.
Rifles, mortars, artillery,machine guns, tanks,airplanes, warships of many types, submarines, airships and dangerousgases.
tanks were used so were, Browning automatics , trench guns (shotguns). AK-47's were not used in WW1. They were invented in 1947. also airplanes were used and submarines. Chemical warfare.
Tanks, Rifles, French Lebel
It was memorable for several new types of weapons technology. It was the first time planes were used as a weapons other then observation of troups. Trench warfare was introduced on a large scale. And because of trench warfare, we had the introduction, for the first time, of tanks and gas as weapons.
Air, land and sea were the types of battles fought in World War 2. They used ships, subs, boats, tanks, large weapons and infantry weapons, fighter planes and bomber planes.
Fighter Planes Tanks Guns