To test the distance of the moon, you can use the ancient Greeks' lunar eclipse plus triangle calculation, but of course this calculation process is still very complicated.

The first step is to prove that both the Earth and the Moon are round, which is not difficult.

The second step is to find two deep wells perpendicular to the ground, separated by two thousand miles in a straight line. Observe the difference in the angle of sunlight entering two deep wells at the same time, because the angle of sunlight entering is different at different locations. Using this angular difference, the distance between the two places is 2,000 miles, and then the circumference and diameter of the earth can be calculated by using pi.

In the third step, the time between the start of the lunar eclipse and the time from the complete obscuration, and the time from the time when the moon is completely obscured to the full moon is fully restored, and the time difference between the two is calculated to be about 3.5 times the diameter of the Earth.

Finally, find a copper coin aimed at the moon, and wait until the copper coin completely obscures the moon. Measure the distance between the eye and the copper coin is 110 times the diameter of the copper coin. Then multiply the diameter of the moon by 110 times, and the distance between the moon and the earth is about 700,000 li.

Of course, the result of this calculation is not absolutely accurate, but it is enough to conquer Ning Zongwu. And the point is that you don't need to use any new mathematical formulas, just pi, and the pi of this world has already been calculated.

It took the ancient Greeks decades to roughly calculate the distance between the moon and the earth, and Du Bian only needed to take their decades of wisdom and turn it into a genius that shocked Ning Zongwu in a few minutes.

......

The second question is still very, very difficult, especially for people in this world, it is simply devastating.

Because this problem needs to be solved by a system of three-dimensional quadratic equations.

It's just a day of age, and the mathematical achievements of this world are not much more advanced than those of normal ancient China, but have regressed slightly. Ordinary elites can add, subtract, multiply and divide is already very remarkable, this Ning Zongwu actually gave a problem of a three-dimensional quadratic equation, are you going to abuse people and cry?

However, this is too simple for Du Bian, and it is completely effortless, after all, he is a former scholar, and he is a master of a prestigious university.

The third question is a history question, and it is a very biased history question.

In the "Book of Feng Zen" in the "Historical Records", it is said: The first emperor was twelve years old after sealing Zen, Qin died, all Confucians were sick and Qin burned poems and books, killed words, and the people complained about the law, and the world was on the side. So who did the king's sacrifice to heaven and earth begin with, and what is the evidence?

This question is definitely a dog, and it can stump most people!

But it just so happened that Du Chang also knew this question, and the answer was Zhou Gong Ji Dan. The evidence is in "Zhou Gong and the Brief Book of Mountains and Rivers", King Wu's body suddenly changed, so he asked his younger brother Ji Dan to sacrifice heaven and earth on his behalf. Only worshipping the heavens becomes a power that only kings or heirs of kings have.

......

These three difficult questions were all solved by Du Bian on his own strength.

However, it also ended here, and he couldn't answer the last seven questions at all, especially the last three questions, which spanned the four disciplines of Xuanqi, Xingchen, Martial Dao, and Alchemy, which was even more like a book from heaven for Du Bian.

In other words, with Du Bian's own strength, he can only get 30 points. Although this score was remarkable enough, there was still a huge gap from the 80 points required by Ning Zongwu, so he still failed, and he couldn't worship Ning Zongwu as a teacher, so he was directly driven away.

This Ning Zongwu, as an ancient person, actually came up with ten such questions, this is not a scholar, he is definitely a demon, and his knowledge is too much ahead of the world.

It was at this time that the old man in white in the dream appeared again, and his face was more serious than ever.

"Ning Zongwu is a very important person, and from him you can dig out the deepest secrets of this world. And this secret is related to your highest mission in coming into this world. ”

Suddenly, Du was stunned.

He just came to apprentice, using Ning Zongwu to improve his alchemy, martial arts, horsemanship, etc. in the shortest possible time, and strive to get the first place in the graduation examination.

As for the highest mission to travel into this world, to be honest, he doesn't care.

"Of course, this is still too far away for you now. The old man in white said: "So you don't have to deliberately dig out his secrets, just become his most proud disciple." ”

Du Bian said: "Ning Zongwu didn't want to accept me as an apprentice, so he gave me ten extremely difficult questions. I tried my best to get only three questions right, and I would definitely be driven away by him. ”

Then, Du Bian put these ten questions in front of the old man in white and said, "There are seven questions left, can you help me solve them?"

"No!" said the old man in white in the dream, "It's all up to you!"

Then he added, "However, I can give you a few books to read, and the answers to these questions are in these books." ”

"Good. Du changed his way.

But the next second he was stunned, because the books that appeared in front of him were more than a meter high.

This...... How many books is this?

For ordinary people, it will take at least a few years to read these books intensively, even if Du Bian has the golden finger of dreaming, he can read at most one-tenth of it.

"First, you completed the task of the crazy gamble and got a reward of ten mental power. So your brain domain is more powerful, and the ratio of dream time to real time will be larger, which means that you can stay in the dream for longer. The old man in white said: "Of course, even so, you can't read all these books overnight, you can only read selectively, and how much you can read depends entirely on your creation." ”

After that, the old man in white disappeared directly.

Then, Du Bian entered the extremely difficult process of hard reading.

You can't read all these dozens of books, you have to read selectively, and you have to touch on the analogy, and you have to know how to think.

He began to read with difficulty, often after reading a few thousand words before entering into long thoughts.

Because of the improvement of mental power, ten hours of reality is almost equivalent to half a month in the dream world, but this time is still not enough.

In the dream, it took five days for Du Yan to find the solution to the fourth question in these books.

It took another four days for Du Bian to find the solution to the fifth question.

It took another three days for Du Bian to find the solution to the sixth question.

It took another three days for Du Bian to find a solution to the seventh problem.

The dream is coming to an end, and Du Chang can solve seven questions. He will soon need to wake up from his dreams, and the rooster outside is already crowing.

Ning Zongwu asked for eighty points, and Du Bian could only complete seventy points, so if he went to the exam like this, he would still fail!

I don't know if it was from the inspiration outside the Nine Heavens Cloud, Du Bian turned to the last page of these books as quickly as possible.

Then, he found that the correct answers to the ten questions were neatly written on them!

True...... Is there really a sentence that my mother sells loquat and I don't know whether to talk about it?

The old man in white's routine is too deep, and he actually tricked Du Chang into reading books for half a month without sleep, his brain is going to dry, and his hair is going to boil white.

He also said that people have to rely on themselves, and as a result, the correct answer is put on the last page. Du Bian could even feel the malicious sneer of the old man in white.

I didn't have time to think about it, Du Bian quickly wrote down the correct answers to these ten questions, over and over again, and after ten full times, he remembered that the score was exactly right.

At this time, the sound of the rooster crowing drilled into his ears, and Du Chang woke up.

It was already three o'clock outside, and Li Wenyu said: "Breakfast has been prepared, but it's too late to eat, and it's going to be late for half an hour." ”

Du Bian hurriedly got up and washed, grabbed a few buns and ran towards the Lotus Temple.

......

Twenty minutes later, Du Bian met Grand Master Ning Zongwu, and he didn't even let Du Bian enter the mountain gate, but directly asked Du Bian to take the apprenticeship exam on a stone table outside the Lotus Temple.

"Ten questions, each 10 points, out of 100 points. Ning Zongwu said: "If you are more than eighty points, you will stay and be my apprentice, otherwise you will leave immediately, and the exam will officially start in one hour!"

Then, Ning Zongwu directly took out an hourglass buckle and put it on the stone table to start the countdown.

Ning Zongwu didn't want to say more than half a word, and he didn't even want to look at Du Bian. Anyway, it is absolutely impossible for Du Bian to pass the assessment, and after the procedure is completed, he will drive people away.

This scene is a bit immediate, how can you, as a great grandmaster, have a tune with Bai Chuan? It's just that his martial arts and knowledge are more than a thousand times higher than Bai Chuan.

Li Wenyu came up to take a look, and suddenly his face turned pale.

What does Ning Zongwu mean by this? He didn't mean to accept Du Cheng as a disciple at all, what was the difference between this and a direct refusal?

These ten questions are completely difficult to get into the sky, right?

Who doesn't know that you Ning Zongwu once had an adventure, so he became an all-round great master. As for the ten questions you asked, how many people in the world can answer eight questions correctly?

Next, Li Wenyu is completely hopeless, Du Bian is a genius, but geniuses also need a learning process. These questions are simply not something that a genius can answer.

Therefore, Li Wenyu has already begun to think of another way in his heart to force Ning Zongwu to accept Du Chengcheng.

And Ning Zongwu closed his eyes and sat beside him, waiting for the end of an hour to drive people away.

......

However, at this time, Du Bian was embarrassed with this difficult test paper, should he take the test 80 points, or should he take the 100 points?

Only half a minute later, Du Chang made a decision, since he became a eunuch, he had completely lost his relationship with the mean. Are the ten permanent servants mean? But they can manipulate the emperor? Are the nine thousand-year-old Wei Zhongxian mediocre? But they beat the civil officials to their knees and call their father.

Moreover, what qualifications do you have as a mere eunuch to be mediocre and low-key? What kind of fame do you have, and whether you have won the title of person or jinshi? This is as ridiculous as a poor man who does not flaunt his wealth.

So, Du Bian began to write and answer questions, which was completely smooth and smooth, and the pen was flying.

One extremely difficult question after another was answered in his pen, and each solution was even more awesome than the standard answer.

The allotted time for answering the question was an hour, but Du Bian had completed it in less than half an hour. This time, I didn't even need to check the answer, and just put the pen down and said, "Great Master, I've finished answering." ”

He knows that there is no need to check the answers, it is an absolute perfect score!

......

Note: Please, please, please, recommendation votes, we only need 100 points, not afraid of pride and no deductions!