Do not reuse from 0 to 9, fill in () below （）+（）＝（）+（）＝（）+（）＝（）+（）＝（）+（）

Do not reuse from 0 to 9, fill in () below （）+（）＝（）+（）＝（）+（）＝（）+（）＝（）+（）

（0）+（9）＝（2）+（7）＝（3）+（6）＝（4）+（5）＝（1）+（8）

Find the rules 1, 4, 5, (), (), 39
Find the number to be filled in brackets

The first four and
1、4、5、10、20、39

28-17+12-8=?

In order to simplify the calculation:
28-17 + 12-8
=28+12-（17+8） =11+12-8
=40-25 =23-8
=15 =15
I wish: learning progress! Come on!

One dial is very common, 12 numbers are arranged on the dial. Four ones are divided into three parts, and the sum of the numbers is the same. How to divide? (the appearance of an ordinary clock, with numbers from 1 to 12 on it)

1 4 9 12=26
2 5 8 11=26
3 6 7 10=26
Do you think so