If you take 35 books from the lower level and put them on the upper level, the books on the upper and lower levels are equal, which means that the lower level has 35× 2 = 70 more books than the upper level. The ratio of books on the upper and lower floors is 2:3, indicating that the lower floor has 3-2 = 1 book more than the upper floor. That is, 1 serving = 70, so that we can find their respective numbers.

Lower layer: 70 ÷ (3-2) × 3 = 2 10.

Upper layer: 70 ÷ (3-2) × 2 = 140 copies.

* * * Book release: 2 10+ 140 = 350.