How many episodes are Mongolian cavalry versus Japanese cavalry?

Mongolian cavalry vs Japanese cavalry is episode 39. In the 39th episode of Eastern Battlefield, Mongolian cavalry clashed with the Japanese Kwantung Army near Nomenkan. The Japanese army assembled hundreds of cavalry and armored soldiers, and launched an attack on the Mongolian army with the cooperation of air force fighters. Most of the Mongolian army suffered casualties. The Soviet government also decided to intervene in the Mongolian war. The Soviet Air Force and the Japanese Kwantung Army launched a large-scale air battle over Nomenkan, which was called the first Nomenkan incident by the Japanese side.