Zhang Ye's Classroom is a small event in Weibo where Zhang Ye posts several problems of a certain level that require critical analysis. Anyone who can answer all questions correctly will win a prize.
Primary School Level[]
When Zhang Ye's wondrous math problem spread throughout Weibo, many netizens asked for Zhang Ye to give them more questions. (Chapter 623: Zhang Ye’s wondrous math lecture!)
Prize: Zhang Ye's autograph or calligraphy pieces
1. Little Zhang is the owner of a shoe shop. A pair of shoes cost ¥20 to buy and sell for ¥30. A customer pays with a ¥50 bill, but as Little Zhang did not have any spare change, he takes the ¥50 to a neighboring shop to change for five ¥10 notes. Finally, he gives ¥20 of change to the customer. Later, when the neighboring shop discovers that the ¥50 note is counterfeit, Little Zhang has no choice but to pay them ¥50. All in all, how much money did Little Zhang lose
2. From 1 to 10, these numbers have been divided into four groups:
1, 3, 7, 8;
10;
5, 9;
2, 4, 6.
Please explain the pattern that was used to separate them into their groups.
3. 7111=0. 8809=6. 2172=0. 6666=4. 1111=0. 2222=0. 0000=4. 5555=0. 8193=3. 8096=5. 4398=3. 9475=1. 9038=4. 3148=2.
Derive the following:
2889=?
4.

College Entrance Examinations level[]
After the Beijing college entrance examinations, Zhang Ye held another "Zhang Ye's Classroom" on Weibo and gave college entrance examinations level questions.
Prized: autograph calligraphy piece from Zhang Ye and a chance to scold Zhang Ye face-to-face for 30 minutes.
Question 1: Essay.
A young man is wandering around at the beach, looking glum.
"Why the long face?" an old man asks.
The young man explained that even though he had always done his best—in life and his work—he had never gotten recognized or respected.
"Watch carefully." The old man picked up a grain of sand and threw it away. "Can you find that grain of sand?"
The young man smiled wryly and shook his head.
"I have here with me a pearl as well." The old man took out a huge pearl and weighed it in his hand, then proceeded to throw it onto the beach. "Now, that won't be difficult to find, right? Become a pearl and no one will ignore you."
—If I become a pearl, no one would ignore me anymore? That made a lot of sense, as the young man thought about it for a moment. Then he picked up the pearl and ran off!
Question requirement: Please use the topic of "Where should the most basic level of trust between people exist?" to write an essay. The is no limitation to how the topic is used, but the essay must not be fewer than 800 words.
Question 2: Mathematics
50 women are performing a square dance in a plaza. They are all spread out 1 meter apart from each other, with the speakers broadcasting at 170 dB. Xiaoming's house is situated on the seventh floor. The current wind speed is 3 m/s.
Question: What is the probability of success should Xiaoming attempt to dump feces on the women in the plaza?
Question 3:
Spring is the season for mating. At 6 PM Beijing time, on the day of the vernal equinox, Police Constable Xiaoli raised his head to the sky at a 38° angle of elevation and saw the North Star. Afterwards, he led his team and rushed into an underground prostitution den to raid it. What are the most likely words that the John in the room would shout out when he realizes that this is a raid?
A. É Dī Gè Shén Ah ["Oh my god" in Guanzhong dialect]
B. Diū Léi Lóu Móu ["F**k your mom" in Cantonese]
C. Nóng Xiǎng Zǔ Sā ["What do you want" in Shanghainese]
D. Ssibal [Motherf*cker/씨발 in Korean]
Question 4:
A BMW sedan with a power rating of 6.0 x 104 watts is traveling on a level highway when it comes to a braking stop 5 meters away from an old granny. The old granny's weight is known to be 50 kg.
Question requirements:
1: Please state the power at which the old granny would fall to the ground at.
2: How much would the old granny demand as compensation?