Mining machine software sells dogs and horses

1. Where there are any tutorials, there are tutorials are deceptive. Just buy a miner and dig according to the instructions. It's not as complicated as you think. Now mining needs professional mining equipment, not a mining software tutorial. Mining is a very professional thing, and the difficulty of mining is also high. If you don't understand, it is recommended not to mine, so as not to be cheated by some illegal pyramid schemes and suffer losses. It is suggested to go to bitcoin home to make up for the common sense of bitcoin
mining is a process of consuming computing resources to process transactions, ensuring network security and keeping everyone's information synchronized in the network. It can be understood as the data center of bitcoin. The difference lies in its completely decentralized design. Miners operate all over the world, and no one can control the network. This process is called "mining" because it is similar to gold panning, because it is also a temporary mechanism for issuing new bitcoin. However, unlike gold panning, bitcoin mining provides rewards for services that ensure the safe operation of payment networks. After the last bitcoin, mining is still necessary.

2.

McDonald's came to China in 1990 and opened its first restaurant in Shenzhen

KFC came to China in 1987 and opened its first restaurant in Qianmen, Beijing

McDonald's (39; s) It is a large multinational chain restaurant in the world. Founded in Chicago in 1955, it has about 30000 branches in the world. It mainly sells hamburgers, French fries, fried chicken, soft drinks, ice procts, salads, fruits and other fast food

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extended information:

business philosophy:

1. KFC's business philosophy is to continuously launch new procts, or repackage the previous sales procts, aiming at people's taste mentality, so as to obtain profits

KFC has the distinction between "high price restaurant" and "low price restaurant". The "original price" printed on all coupons is the price of "low price restaurant", and the price of each item in "high price restaurant" is about 10% higher than the "original price"

2. McDonald's

the revenue of McDonald's company mainly comes from the real estate operation revenue, the service fee collected from franchise stores and the surplus of Direct stores

because the franchisees generally do not have enough funds to pay the land cost of US $30000 and the construction cost of US $40000, they are often unable to obtain loans. McDonald's company is responsible for looking for a suitable location for franchisees, renting or purchasing land and houses for a long time, and then renting the stores to franchisees to get the difference. This is the main source of McDonald's revenue

The essence of this is that McDonald's real estate company (a company established to implement the real estate strategy) buys real estate with the money of each franchise store, and then rents it to the franchise store. This kind of real estate management strategy actually transfers the rights of the first creditor to McDonald's real estate company, so that it can have the qualification to obtain loans from the bank

source of reference: Internet - McDonald's

source of reference: Internet - KFC

3.

Let me give you a name for your data. The first column is called illness, the second column is called health, the first row is called smoking, and the second row is called no smoking

In order to calculate the theoretical frequency, the theoretical probability should be calculated first. Here you have 200 people, 82 of whom are sick and 128 of whom are not, so the theoretical probability of being sick is 82 / 200 and the theoretical probability of not being sick is 128 / 200.

then you divide these 200 people into two groups, smoking and non-smoking. There are 100 smokers in this group. According to the theoretical probability, the number of patients in this group should be 100 * (82 / 200). So we can calculate the theoretical frequency of smoking and getting sick

Similarly, smoking should be 100 * (128 / 200). The rest is the same

extended data:

the theoretical frequency is also known as the empirical frequency. The statistical concept refers to the estimation of the actual frequency by using the positive theoretical rate

The chi square test is used to compare two rates or two constituent ratios

1. Special formula:

if the frequency of four cells of four cell table data is a, B, C, D respectively, then the chi square value of chi square test of four cell table data = n (AD BC) ^ 2 / (a + b) (c + D) (a + C) (B + D), (or use the fitting degree formula)

degree of freedom v = (number of rows - 1) (number of columns - 1) = 1

2. Application conditions:

it is required that the sample size should be greater than 40 and the theoretical frequency in each lattice should not be less than 5. When the sample size is more than 40 but 1 = & lt; Theoretical frequency & lt; When the sample size is less than 40 or the theoretical frequency is less than 1, the exact probability method can only be used to calculate the probability

OK × Chi square test of tabular data is used to compare multiple rates or constituent ratios

Special formula:

the chi square value of chi square test of C-list data in row r = n [(a11 / N1N1 + A12 / N1N2 +... + arc / nrnc) - 1]

2. Application conditions:

it is required that the theoretical frequency t in each lattice is greater than 5 or 1 & lt; T< The lattice number of 5 is not more than 1 / 5 of the total lattice number. When T & lt; 1 or 1 & lt; T< When there are more grids of 5, we can use parallel parallel, delete row, delete column, and increase the sample content to make them conform to the row × Application conditions of chi square test for tabular data. The comparison of multiple rates can adopt the method of row x list segmentation

4. Corresponding to the real measurement data of the first item in the experiment, when US1 acts alone, K2 connects two points of the right double pole switch (that is, US2 is short circuited), and the total current is I1 & # 39= US1 / [R1 + (R2 and R3)]
= 10 / [200 + (300 / / 510)] = 10 / (200 + 189) = 25.7ma< br />-i2'= The total current is XR3 / (R2 + R3) = 25.7x510 / (300 + 510) = 16.2ma< br />i3'= Total current XR2 / (R2 + R3) = 9.5ma, or I3 & # 39= The total current is - I2 & # 39< br />Uab'= i1' x R1=5.14v，Ubc'= Ubd'=- I2 x R2 = 4.86v or I3 x R3 = 4.86v
corresponding to the second real measurement data, when US2 acts alone, K1 connects two points of the left double pole switch (that is, US1 is short circuited), and the total current is I2 & # 39&# 39;= US2 / [R2 + (R1 and R3)] = 6 / [300 + (200 / / 510)] = 10 / (300 + 144) = 13.5ma< br />-i1'&# 39;= The total current XR3 / (R1 + R3) = 13.5x510/710 = 9.7ma< br />i3"= The total current XR1 / (R1 + R3) = 13.5x200/710 = 3.8ma< br />Uab"= i1" x R1=-9.7x200=-1.95v，Ubd"= i3" XR3 = 1.95V, or UAB = - UBD< br />Ubc"=- i2" xR2=-13.5x300=4.05v
corresponding to the third term, the KVL and KCl equations are listed
I1 & quot&# 39;+ i2'&# 39;&# 39;= i3'&# 39;&# 39;..............( 1)
us1=i1'&# 39;&# 39; R1+i3'&# 39;&# 39; R3............(2)
us2=i2'&# 39;&# 39; R2+i3'&# 39;&# 39; R3...... (3)
by solving the equation, we can get the data of the third term when two power sources work together.

5. ⊕ theoretical plate number (n) is used to quantitatively express the separation efficiency of chromatographic column
n depends on the type of stationary phase, properties (particle size, particle size distribution, etc.), filling condition, column length, type and flow rate of mobile phase, and properties of substances used to determine column efficiency. If the peak shape is symmetric and conforms to the normal distribution, n can be approximately expressed as:
n = (TR)/ σ 2 = 16 (TR) 2 / w = 5.54 (TR / W1 / 2) 2
W: peak width; σ： Half of the peak width at the inflection point of the curve, that is, half of the peak width at the peak height of 0.607
when n is a constant, W is proportional to tr. On a multicomponent chromatogram, if the content of each component is equal, the peak of post elution will graally widen and the peak height will graally decrease
it is more convenient and commonly used to calculate the number of theoretical plates with half peak width than with peak width, because half peak width is easier to accurately determine, especially for the slightly trailing peaks
n is proportional to the column length, and the longer the column is, the larger the n is. When n is used to indicate column efficiency, the column length shall be indicated. If n is not indicated, the number of theoretical plates when the column length is 1m shall be indicated Generally, the N content of HPLC column is more than 1000
if the adjusted retention time (TR ') is used to calculate the theoretical plate number, the value obtained is called effective theoretical plate number (n or Neff) = 16 (TR' / W) 2
⊕ variance of theoretical plate height (H) per unit column length. H= In practical application, the column length L and the number of theoretical plates are often used to calculate: H = L / N
in practical application, it is enough to achieve complete separation. If the number of plates exceeds, the test time will increase, and the test efficiency will decrease.

6. The formula:
1.86 + (1 + 0.1) ^ n = 10, calculate the value of n

7. The number of tiles is generally roughly calculated now, because there will be certain loss in the process of tile paving. So when you buy ceramic tiles, you just need to tell the actual size of your home to the tile seller, and he will calculate it for you.

8. 1
according to the approximate calculation of the chemical theoretical volume fraction, the chemical theoretical volume fraction can be used to determine the lower explosion limit of alkanes when the explosion gas is completely burned. The formula is as follows:
L ≈ 0.55c0
where
0.55 -- constant
C0 -- chemical theoretical volume fraction of explosive gas in complete combustion. If the volume fraction of oxygen in the air is 20.9%, C0 can be determined by the following formula:
C0 = 20.9 / (0.209 + N0)
where
N0 -- the number of oxygen molecules required for complete combustion of combustible gas
for example, in the case of methane combustion, the reaction formula is
CH4 + 2O2 → CO2 + 2H2O
then N0 = 2
then l = 0.55 × 9 / (0.209 + 2) = 5.2, the difference between the calculated value and the experimental value is less than 10%<
2
for the calculation of explosion limit of two or more combustible gases or combustible vapor mixtures, there are two recognized calculation methods at present:
2.1
1? Chatel's law
for two or more combustible vapor mixtures, if the explosion limit of each combustible gas is known, then according to Lai? According to Chatel's law, the explosion limit of gas mixed with air can be calculated. When PN is used to express the volume fraction of a combustible gas in the mixture,
LEL = (P1 + P2 + P3) / (P1 / lel1 + P2 / lel2 + P3 / lel3)
(v%)
upper explosion limit of mixed combustible gas:
uel = (P1 + P2 + P3) / (P1 / uel1 + P2 / uel2 + P3 / uel3)
(v%)
this law has been proved to be valid
2.2
Management? Chatterley formula? ChaTry believes that the explosion limit of combustible gas or vapor mixture with complex composition can be calculated according to the known explosion limit of each component according to the following formula. The formula is applicable to the combustible gas mixture which does not react with each other and has no catalytic effect ring combustion
LM = 100 / (V1 / L1 + V2 / L2 +... + VN / LN)
where LM -- explosion limit of mixed gas,%
L1, L2, L3 -- explosion limits of each component in the mixed gas,%
V1, V2, V3 -- volume fraction of each component in the mixed gas,%< For example, the composition of natural gas is as follows: methane 80% (L = 5.0%), ethane 15% (L = 3.22%), propane 4% (L = 2.37%) and butane 1% (L = 1.86%)
LM = 100 / (80 / 5 + 15 / 3.22 + 4 / 2.37 + 1 / 1.86) = 4.369
3
combustible st
the lower explosion limit of many instrial combustible st is between 20-60g / m3, and the upper explosion limit is between 2-6kg / m3
If hydrocarbon st can be completely vaporized and burned out, the lower explosion limit can be calculated by the Burgess Weiler relation:
C × Q = k
where C is the lower explosion limit concentration
Q -- combustion heat per mole or per gram of the substance.

9. Count the numbers