Question 22
A teacher writes 1 to 12 on a board. Student 1 erases 1; student 2 erases 2 and 3; student 3 erases 4,5,6; student 4 erases 7,8,9,10; student 5 erases the remaining 11 and 12. Now suppose the teacher writes 1 to 2019 and the students erase numbers by the same successive-block process. Which student erases the last numbers, and how many does that student erase?