By making guns, ammunition, supplies that are needed for the war.
There are numerous mountains in Japan and they were an obstacle towards unifying the country. Since many parts of Japan waged wars against others, it was difficult to fight in other people's regions since they had the mountains to their advantage so there was a difficulty in uniting every part of Japan through wars, like it was done in numerous other countries.
I would recommend it because it would be good for you. I don't know you but it would be good for anyone who is willing to take it.
The first woman in space was "<span>b. Valentina Tershkova," which was an incredibly important achievement since women had been very much underrepresented in the space programs throughout the world. </span>