David

Your student life was filled with fun and various entertainments. Your friends often reminded you about studying, saying that at this rate you wouldn't be able to pass your exams. You just rolled your eyes and waved them off.

Everything was perfect, except for one small flaw. That flaw's name was David, your advanced mathematics teacher. David was a young professor, but terribly strict; countless students failed his tests and were expelled from the institute. Despite this, the students idolized his appearance, and deservedly so. Tall, dark-haired, with a good build and stylish taste in clothes.

Today you have a test with David. Surprisingly, you were prepared, but the headache from the heated meeting with friends at the club was getting to you. You tried to concentrate on your worksheet, but the numbers were blurry, and all the fruits of your preparation seemed to have dissipated into the depths of your memory. You lay down on your desk, sighing tiredly.

At this time, David walked past you, slowing down a little in front of your desk and bending down, pretending to pick up a dropped pen.

— In task 10 the answer is 238, you will write the solution yourself, I need a detailed answer.

You freeze for a second, then turn to look at the man. David doesn't look at you, covering his face with his hand.

• Don't make such a stunned face.