Given the set M = {x | x = 3N, n ∈ Z}, n = {x | x = 3N + 1, n ∈ Z}, P = {x | x = 3n-1, n ∈ Z}, and a ∈ m, B ∈ m, C ∈ P, and d = a-b + C, then (). A.D ∈ m B.D ∈ n C.D ∈ P D, | Math enthusiast | Mathematical art

Given the set M = {x | x = 3N, n ∈ Z}, n = {x | x = 3N + 1, n ∈ Z}, P = {x | x = 3n-1, n ∈ Z}, and a ∈ m, B ∈ m, C ∈ P, and d = a-b + C, then (). A.D ∈ m B.D ∈ n C.D ∈ P D,

a=3l,b=3m+1,c=3n-1, l,m,n∈Z
d=3l-(3m+1)+3n-1=3(l+n-m)-2=3(l+n-m-1)+1
And L + n-m-1 ∈ Z
So D ∈ n, choose B

RELATED INFORMATIONS

1. There are several books on both bookshelves A and B. If you take 100 books from bookshelf B and put them on bookshelf a, the books on bookshelf a are five times more than those on bookshelf B. If you take 50 books from bookshelf A and put them on bookshelf B, the books on both bookshelves are the same. How many books are there on each bookshelf, Linear equation of one variable
2. This is a test question of binary linear equations A new operation "*" is defined for real numbers x and Y. x * y = ax + by (A and B are constants). On the right side of the equation are the usual addition and multiplication operations. It is known that 3 * 5 = 15 and 4 * 7 = 28. What is a + B?
3. If the figure is a hexagon composed of nine equilateral triangles, it is known that the side length of the smallest equilateral triangle in the middle is a, then the circumference of the enclosed hexagon is () A. 30ab. 32AC. 34ad
4. How many fifth grade Olympiad math questions are urgent! Good hearted people come! The distance between two places on a river is 280 meters. A ship sails between them. It takes 14 hours to sail downstream and 20 hours to sail upstream. Find out the ship's velocity and current velocity in still water
5. 1. The East and West towns are 240 km apart. A bus leaves from the East Town at 8 am and a truck leaves from the West Town at 9 am. By 12 noon, the two cars just meet at the middle point between the two towns. If the two cars leave each other from 8 am to 10 am, the two cars will stop at the middle point between the two towns, How many kilometers are there between the two cars? 2. Car a and car B drive in the opposite direction from the midpoint between the East Village and the West Village at the same time. Six hours later, car a arrives at the East Village, and car B is 42 kilometers away from the West Village. It is known that car a's speed is twice that of car B. how long is the road between the East Village and the West Village? Please do not use the equation solution, use the general formula or comprehensive formula, please write the answer of the formula
6. Is there any kind-hearted person who can help me solve a math problem? The hedgehog can pick 20 pinecones every day in sunny days and 12 pinecones in rainy days. It can pick 88 pinecones for 6 consecutive days. How many days are there in sunny days and how many days are there in rainy days?
7. Fill in the figure below with 5 / 12, 5 / 8, 2 / 5, 1 / 15, 11 / 40 to make the sum of the fractions in the two circles on each line equal Hehe is 5 / 12, 5 / 8, 2 / 5, 1 / 15, 11 / 40, 7 / 24
8. A cuboid, 5 cm longer, becomes a cube, and its surface area increases by 160 square cm. What is the volume of this cuboid______ Cubic centimeter
9. The math problems in volume two of junior high school are due this afternoon Sorry, I don't have points, so I can't give points. But I hope you can help me solve it 1. If an inner angle of a polygon with equal angles is n times of its outer angle, then the number of sides of the polygon is () A. It doesn't exist B、2N+2 C、2N-1 D. None of the above is true 2. In △ ABC, BP bisects ∠ B and CP bisects ∠ C. If ∠ a = 60 degrees, ∠ BPC = () 3. If the sum of interior angles of a polygon is 1260 degrees, then there are () diagonals passing through a vertex of the polygon 4. (n-k) M = ()
10. Some math problems in Volume 2 of junior high school (fill in the blanks) 1. If 2x-y = - 3, then the x power of 4 and the Y power of 2 = () 2. If m power of x = 2 and N power of x = 3, then 2m + n power of x = () 3. Given that the square of the algebraic formula 4x - (k-1) XY + 9y is a complete square, then k = () 4. If 2m power of x = 3, then 6m power of x = () thank you.
11. You need someone with a good head to answer this math problem There are six passengers on the train from Beijing to Guangzhou. A, B, C, D, e and F are from Beijing, Tianjin, Shanghai, Yangzhou, Nanjing and Hangzhou A and Beijing people are doctors, e and Tianjin people are teachers, C and Shanghai people are engineers; A. B, F and Yangzhou have been in the army, while Shanghai people have never been in the army; Nanjing people are older than a, Hangzhou people are older than B, and F is the youngest; B to Wuhan with Beijingers, C to Guangzhou with nanjingers According to the known conditions to determine each passenger from the city and occupation
12. Ask enthusiastic people to help answer A stationery store. If you buy more than 300 pens at a time, excluding 100 pens, you can buy them at wholesale price. Buy less than 300 pens and sell them at retail price. Xiao Ming buys pencils in the shop. If you buy one for everyone in the school. It can only be sold at retail price. It's 120 yuan. If you buy 60 more pens, you can buy them at the wholesale price. It will also cost 120 yuan. So. What's the size of this school. 2. If the purchase price of 6 pens at retail price is the same as that of 5 pens at wholesale price, how many people are there
13. On a straight road, two cars go in the same direction. At the beginning, car a is 4km in front of car B. the speed of car a is 45km / h, and that of car B is 60km / h. how many meters is the distance between the two cars one minute before car B catches up with car a? First order equation with one variable is solved,
14. 1, the standard equation of hyperbola 7x ^ 2 - 2Y ^ 2 + 8 = 0 is - the coordinate of intersection is—— 2. Ask for the hyperbolic standard equation of points F1 (0. - 5), F2 (0.5) and passing through point a (0.3)—— 3. On the hyperbola 4x ^ 2 - y ^ 2 + 64 = 0, the distance from a point P to one of its focal points is equal to 1. Then the distance from point P to another focal point is equal to 1———— I have run out of marks. I have no choice
15. Xiaohong's family wants to make a cuboid open glass fish tank that is 70cm long, 50cm wide and 65cm high (glass thickness is ignored) 1. Please help Xiao Hong calculate how many square decimeters of glass is needed to make this fish tank? 2. Pour some water into the fish tank. The height of the water is 25cm from the mouth of the fish tank. How many liters of water are poured into the fish tank? 3. When some small stones are put into the fish tank, the water surface rises by 10 cm. What is the volume of small stones in cubic decimeters? 4. How many centimeters of colored light line is needed to surround the upper edge of the fish tank with a circle of colored light line? If you have a good answer, you can add extra points!
16. The summer vacation lasts 64 days. Xiaoming plans to spend 18 days on painting, 16 days on calligraphy, 10 days on tourism and 20 days on others 1. What percentage of the total holiday days are painting, calligraphy and tourism? 2. How many days did you spend on painting and calligraphy? 3. How many more days do you spend studying calligraphy than traveling?
17. Uncle Zhang walked 20 kilometers in three hours. How many kilometers per hour on average? Expressed in fractions 2. Jiang Li used six pieces of paper to fold eight thousand paper cranes, and the Palace used eight pieces of paper to fold six thousand paper cranes How many pieces of paper does Jiang Li use per thousand paper cranes? Who folded a thousand paper cranes?
18. A happy Frenchman was traveling in Russia. He took some money with him and came to a restaurant. He borrowed the same amount of money from the owner of the restaurant and spent one rouble. With the rest of the money, he went to the second hotel, where he borrowed the same amount of money and spent one rouble. Then he went to the third and fourth hotels and did the same thing, When he came out of the fourth restaurant, he had nothing left. How much did the cheerful Frenchman have?
19. There is a section of uphill and a section of level road from a to B. if the uphill is 3km per hour, the level road is 4km per hour, and the downhill is 5km per hour, then it takes 54 minutes to go from a to B and 42 minutes to go from B to A. what is the total distance from a to B? I think the answer is: 54 minutes = 0.9 hours, 42 minutes = 0.7 hours, the time for leveling is x hours. The equation is: 3 (0.9-x) + 4x = 4x + 5 (0.7-x) to get x = 0.4 hours, the whole journey is 3.1 km
20. The total land area of the world is about 14900 square kilometers, and Asia accounts for 29.5%. Asia has a population of 4.07 billion people. Q: how many square kilometers of land area does each person occupy The total land area of the world is not 14900 square kilometers, it is 1490 million square kilometers!