1,6,5,7,2,8,6,9 () what do you fill in the brackets?

The answer is 3
a(n)=a(n-1)-a(n-2) n=2k,k>0
5=6-1
2=7-5
6=8-2
()=9-6

1 () 2 () 3 () 4 () 5 () 6 () 7 () 8 () 9 = 100, add, subtract, multiply and divide, or add brackets to make the equation hold

Sincerely answer your question:
1（+）2（+）3（+）4（+）5（-）6（-）7（+）8（+）9（×）10=100

How to simplify the calculation of 4.78 △ 0.25 + 5.22 × 4

4.78÷0.25+5.22×4
=4.78×4+5.22×4
=(4.78+5.22)×4
=10×4
=40

Nuclear power plants use nuclear energy to convert into electric energy. Why can't chemical energy be converted into electric energy? What's the difference between nuclear energy and chemical energy?

Chemical reaction: molecular rupture and atomic recombination
The nuclear reaction of nuclear power station is the rupture of atom (nuclear fission), which produces new material, but it is essentially different from chemical reaction

(1 + 40%) times x times 80% - x = 15

4 × 0.8-x = 15
1.12x-x=15
0.12x=15
3/25x=15
x=15×25/3
x=125

How to improve the efficiency of converting wind energy into mechanical energy for windmills

Reduce mechanical friction

On the problem of dimensional space
After reading the quantum apocalypse, there are some problems. I'm not good at learning. I've heard a saying that if I travel through time and space, my mind can't go back to my past body. That is to say, after I travel through time, I will see another self. This is parallel space overturning the situation I said in the first half of the sentence But if it is possible for my consciousness to go back to the carrier of the past, why? Or is it impossible at all?
What is the reason why as like as two peas, he will return to his milk for a moment? If he enters a high latitude space, he should be able to see a person exactly like him? And there should be 673... Maybe there should be countless It's a mess
Someone told me that the time point of 1234567 latitude is the same, while the latitude of 891011 can cross the past and the future. Does that mean that men are not only the fifth dimension?
There is another problem, that is, how does the seventh dimension and the sixth dimension transition? I say that when I look at the sixth dimension in the seventh dimension, it is like looking at an ant on a piece of paper. The paper is countless parallel spaces, but I can see all the paper in the seventh dimension, that is, all the universes, but the seventh dimension can only see one piece of paper, that is, limited parallel space, What's the difference between this paper and that paper? If the paper seen in the sixth dimension is a plane, and what I saw in the seventh dimension is a three-dimensional paper, what's the difference between this plane and three-dimensional paper? Because theoretically, the seventh and sixth are all outside the plane universe, Isn't that the same? What does the seventh dimension add to the sixth dimension to distinguish them?
In the penultimate line, the sentence "the seventh dimension can only see a piece of paper, that is, limited parallel space", "seven" is changed to "six"

First: you're watching a movie. Don't take it too seriously
Second: first go to see Hawking's brief history of time, and then study movies
Third

How many jin is an ounce?
Can you give a popular example? Like the weight of something?

Ounces are divided into troy ounces and troy ounces
1 troy ounces = 31.1035g, 1 troy ounces = 28.3495g
One Jin = 500g = 16.0754 troy ounces = 17.6370 troy ounces
50 grams is one or two, 30 grams is six
Half the weight of an egg is close to 30 grams
Because a jin of eggs can be weighed about 7 or 8
or
Find 6 new coins of 5 cents. They are standard 5 grams each. Hold 6 coins in your hand and you can weigh 30 grams
note appended:
interpretation:
(1) Ounce (abbreviation oz), English translation of ounce, translated from Hong Kong as an English unit of weight, is one sixteenth of a pound
(2) A unit of mass equal to one sixteenth of a pound or approximately 28.3495 grams
(3) A unit of mass in the system of Pharmacopeia or Troy, equal to 480 grains or 31.1034768 grams
Classification and conversion
Troy ounces: a unit of weight oz.tr It is commonly used in the measurement of precious metals such as gold and silver
1 oz = 31.1035 G
12 ounces = 1 lbs
"Ounces" is the international common unit of gold measurement
An ounce is about one or two times as large as the old Chinese weights and measures
In the old system, the amount of gold received by banks under the old system of weights and measures was equal to 1.0047 ounces, which means that the old system of weights and measures is a little more than 1 ounces. Now under the new system of weights and measures, 1 ounces is equal to 31.1039 grams, which is equal to 0.622 ounces of the kilogram system
Troy ounces: a unit of weight oz.av .
1 oz = 28.350 G
1 oz = 16 DRAM
16 ounces = 1 pound
Troy ounces: unit of weight, abbreviated as AP oz
1 oz = 31.1030 G
Liquid ounces: unit of measure of capacity, symbol oz
1 British liquid ounces = 28.3495231 ml
1 US liquid ounces = 29.571 ml

Factorization of a & # 179; - 9b + 9A + A & # 178; b

a³-9b-9a+a²b
=a³-9a+a²b-9b
=a(a²-9)+b(a²-9)
=(a+b)(a²-9)
=(a+b)(a+3)(a-3)

Given the ratio of voltage, the sum of electric power and one of the electric power, find the ratio of resistance and electric power

Series connection: the current is equal everywhere, the resistance shares the voltage together, u = I * r, resistance ratio = voltage ratio, P = I * I * r, electric power ratio = resistance ratio; parallel connection: the terminal voltage is equal, U1 = U2, P = u * U / R, electric power ratio = reciprocal of resistance ratio, for example, (P1 + P2): P1 = A: B, then AP1 = BP1 + bp2, so P1:

1,6,5,7,2,8,6,9 () what do you fill in the brackets?