How many grades does world of tanks need to upgrade its buildings within 24 hours?
World of tanks's 24-hour open bonus will raise the building to several levels and above level 3. Official website introduced that in the game of "world of tanks", 24-hour bonus can only be started if the command center level is upgraded to level 3 or above. Specifically, players need to build and upgrade the command center, factories, warehouses and other buildings in the game to improve their level. If they reach level 3 or above, they can start a 24-hour bonus.