1. What is its name?
This is a T-34 Light Tank.
2. When was it build?
This tank was developed in 1934 by the Factory #185 in Leningrad.
3. How it was armed?
It was intended to arm with a 20-mm automatic tank cannon, but never armed with it because at that time there was no such cannon available. The tank was armed with the 7.62-mm DT machine-gun. A single photo of the T-34 with a 20-mm cannon was found in archives. After that some sources claimed this tank was later re-armed. I must insist however, that was not a cannon but a wooden mock-up.
1. What is this? (if you don't know the proper English term but know how this thing works, you may describe it)
This is the Soviet 90/78 rifled projectile. Rifled projectiles were developed in the middle of the 19th century in hope they will provide with extra accuracy. In Russia (and USSR) such projectiles called "polygonal" due to their form.
1. What is the name of this beast?
This is the ISU-130 Heavy Assault Gun.
2. What is calibre of his gun?
It is armed with a 130-mm Gun adapted from the naval gun.