- Title: The Most Difficult Problem Set: Japanese Language Arts, Grade 5, Part 2 (Lower) - Publisher: Yotsuya Otsuka ☆ Retail Price: 1760 yen (tax included) ☆ Never used. No writing, stains, or tears are visible. However, there are some minor dents and scratches on the front and back covers. Also, please note that this item has been stored at home, so please consider this before purchasing.＾＾