Red dragon: in charge of natural disasters

I have an exam tomorrow, I need to take a day off

I haven't made up for the last one, I feel so ashamed.

But learning operations research gave me a headache, I turned on the computer and sat in front of the screen for a long time, I felt dazed and couldn't type a single word.

And for some reason, I've been in a bad mood recently.

I'm very sorry. (End of this chapter)