Senior elementary school classmate , please

I think this kind of thing happens everywhere, for example, in our class, the class cadres in the class are all ...... who are poor in learning, bad in character, and low in perceptionThis is very good, students who study well and perform well will not only not be proud, but will work harder, and students who study poorly and perform poorly will converge their behavior and be conscious after becoming class cadres, because people will have low self-esteem, and they will cheer up more after seeing other students work hard, so this may be the teacher's painstaking position, even if it is not, it will be regarded as yes! It's also good under psychological comfort.

I think it is not very appropriate for primary school students, after all, primary school students' self-discrimination ability is not very strong, they find that the appointed class cadres are not as good as they think, or even worse than them, they may lose confidence in learning or other activities, and have resistance to the work of teachers and classmates, which is not conducive to the formation of a united air, nor is it conducive to the unhindered communication between classmates. On the contrary, they themselves have not performed well.

So, I think it's better to think carefully.

You can let them exercise themselves, and maybe they will be more strict with themselves than before!

For primary school students, it is not very good, although the appointment of class cadres is also an affirmation of a person and an appreciation for him, but they still know little after all. The main question is are you sure the person is not performing well? There are many aspects of poor performance, and if it is only in terms of academic performance, then it is safe to appoint.

There are two sides, so that she can control herself as well as others.

The key to whether it is good or not lies in the teacher's teaching.

The burrows of grasshoppers are in some small mounds or bricks, and grass insects have black beetles, small round worms, etc.

I'm sorry......The grasshopper's burrow is in **I don't know ...... eitherBut I still know what grass insects are—insects that inhabit grasses, such as crickets, grasshoppers, beetles, etc.

1.Ecstatic 2Elation 3Palature 4Precious foreign gas 5Poverty and incompetence 6Invigorate China.

After hearing the news of the liberation of the motherland, Hua Luogeng, who was (patriotic as home), gave up his (luxurious and magnificent) house and (luxurious) car and returned to the motherland (thinking day and night) in order to (revitalize China).

Journey: 160 4/7 = 280 (km).

Car B: 280 quarters = 70 (km).

160 4 7 = 280 km Distance between two places.

280 1 4 = 70 km The distance traveled by the second vehicle.

Distance: 160 4 7 = 280 km.

The second car: 280*1 4=70 km.

Total distance = 160 4/7 = 280km, that is, the distance between A and B is 280km

then the distance traveled by the second car = 280 quarters = 70km

Arithmetic 160 4 7 280 km 280 1 4 70 km The second equation is solved in kilometers. 4 7 160 280 280 1 4 70 km

The distance between A and B is 160 (4, 7) 280 (km), and the distance traveled by the second car is 280 (1, 4) 70 (km).

b 1:1

Reason: Pi is the ratio of circumference to diameter and is a constant (

The ratio of the pi of a circle with a diameter of 5 cm to the pi of a circle with a diameter of 1 m is (:1).

Hello Creative Home Boutique.

The ratio of pi of a circle with a diameter of 5 cm to a circle with a diameter of 1 m is (b).

Because pi is constant, pi (pronounced pài) is a constant (approximately equal to.

The pi of the circle = the circumference of the circle The diameter of the circle, which is a fixed value.

We hope you are satisfied.

There is only one pi, and pi is the same,。。 Infinite does not loop decimals, so it's one to one, choose b

Choose 1:1 because pi refers to the ratio of circumference to diameter in the same circle. Regardless of the size of the circle.

Correct is b because pi is a constant that is fixed and unchanging

Pi is a vulture, and its value is a fixed value

Pi is a fixed value regardless of the size of the circle, so choose (b).

1:1 because pi does not change under any circumstances.

Pi is a fixed value, and B is selected regardless of radius

Pi is constant, so choose B

The answer is b.

Pi, generally expressed as , is a mathematical constant. It is definite and unchanging.

So the ratio of two pi is 1:1

Because pi is constant at all times, B should be chosen

b, should be pi independent of the radius of the diameter.

Pi is a constant number, so it's 1:1

Select b Pi has nothing to do with the size of the circle, it is a fixed value.

b Pi is a fixed value and has nothing to do with the diameter of the circle.

1 Cement: sand: gravel = 2:3:5

2.Cement 240 2 10 = 48 tons.

Yellow sand 240 3 10 = 72 tons.

Pebbles 240 5 10 = 120 tons.

3.There are a total of 21 3 10 = 70 tons of concrete material and 70 tons of cement should be used 70 2 10 = 14 tons, so there are still 21 14 = 7 tons of stone should be used 70 5 10 = 35 tons, so there is nothing left!

1. Cement: yellow bai

Sand: Pebble = 2:3:5

2, cement DU240 2 10 = 48 tons of yellow sand 240 3 10 = 72 tons.

Pebbles 240 5 10 = 120 tons.

3, when the dao yellow sand is all used up, the cement uses its back 2 3, and the stone uses its 5 3.

Cement used: 21x2 3=14 tons.

Cement left: 21-14 = 7 tons.

Stone used: 21x5 3 = 35 tons.

Stone also needed: 35-21 = 14 tons.

A: There are 7 tons of cement left. The stone also needs 14 tons.

1. Cement: Huangsha du: zhi stone 3 5 dao10 (parts).

Within 240 10 24 (t).

Cement is: 24 2 48 (tons).

The yellow sand capacity is: 24 3 72 (tons).

The pebbles are: 24 5 120 (tons).

3 7 (times).

Cement remaining: 21 2 7 7 (tons).

Stones also need: 5 7 21 14 (tons).

1 . 2:3:5

2.Cement: 240 x (2+3+5)BAI2 = 48 (tons) of copy fractions

Yellow sand: 240 x (2+3+5) 3/3 = 72 (tons) Stone du: 240 x (2+3+5) 5/5 = 108 (tons) A:

It is necessary to prepare 48 tons of cement, 72 tons of yellow sand, and 108 tons of stones. DAO tons) 7 x (3-2) = 7 (tons).

7 x (5-3) = 14 (t).

A: There are 7 tons of cement left, and 14 tons of stones.

:3:5

3. Cement leftover: 21-(21 3*2) = 7 tons.

Stone need: 21 3 * 5-21 = 14 tons.

1.The three materials are prepared according to the ratio of cement: yellow sand: stone = 2:3:5.

2.To prepare 240 tons of concrete, 48 tons of cement, 72 tons of yellow sand and 120 tons of stone are required.

Answer: 240 tons 10 parts = 24 tons, cement in the concrete accounts for 2 parts 24 * 2 parts = 48 tons, the same way to calculate the tonnage of other materials.

3.There are 7 tons of cement left, and 14 tons of stone are needed, and the calculation is as follows:

Yellow sand accounts for 3 parts in the concrete, and each part is 21 tons when it is used up, 3 parts = 7 tons; According to the proportion, 2 parts of cement are 7 tons * 2 parts = 14 tons, so there are 7 tons left; 5 parts of the stone are needed for a total of 7 tons * 5 parts = 35 tons, so 35 tons - 21 tons = 14 tons are needed.

1 Cement.

Yellow baisha: Stone = 2:3:5

2.Cement 240 2 10 = 48 tons.

du yellow sand zhi240 3 10 = 72 tons.

Pebbles 240 5 10 = 120 tons.

3.There are mud daos in total

Soil plate 21 3 10 = 70 tons.

The cement right should be 70 2 10 = 14 tons, so the remaining 21 14 = 7 tons of stone should be 70 5 10 = 35 tons

1. Cement: yellow sand.

bai: The ratio of stones is 2:3:5;

du2, to configure 240 tons of such a mixture

concrete, cement DAO is 240 2 (2 + 3 + 5) = 48 tons, yellow sand back is 240 3 (2 + 3 + 5) = 72 tons, and stone A 240 5 (2 + 3 + 5) = 120 tons;

3, set the cement remaining x, the stone still needs y, 2:3:5=(21-x): 21:(21+y),21-x=14,x=7,21+y=35,y=14

1.The three materials are matched in a ratio of 2:3:5.

2.Cement: (2 10) * 240 = 48; （3/10）*240=72; (5/10)*240=120

er cement left 7 tons, lion.

The sub needs to be 14 tons inside.

Remember to reward points.

A1 2:3:5

2 2 + 3 + 5 = 10 (portions).

The "bai" below represents the score line.

Cement duzhi: dao240x1 5 = 48 (tons).

Yellow sand: 240x3 10 = 72 (tons).

Stones: 240x1 2=120 (tons).

A: 48 tons of cement, 72 tons of yellow sand, and 120 tons of gravel are needed.

The following " " stands for division.

3 There are 7 tons of cement left, and 14 tons of stones are needed, and the calculation is as follows:

Yellow sand accounts for 3 parts in the concrete, and each part is 21 3 = 7 (tons) when it is used up; According to the proportion, 2 parts of cement are 7x2 = 14 (tons), so there are 7 tons left; 5 parts of the stone are needed for a total of 7x5 = 35 (tons), so 35-21 = 14 (tons) are also needed.

Hope it helps.

：du3：5

3+5=10 240*2/10 = 48 tons zhi 240*3/10 = 72 tons 240*5/10 = 120 tons *3=7 cement 7*2=14 tons 21-14=7 tons Stones: dao7*5=35 tons 35-21=14 tons.

1: The three materials of this concrete are formulated according to 2:3:5.

Mud: 240x (2 10) = 48 (ton capacity).

Sand: 240x (3 10) = 72 (tons).

Stone: 240x(5 10)=120 (tons).

Please understand that I am not very good at doing question 3.

1. The three materials of this bai kind of concrete are prepared according to DU2:3:5.

2. To prepare 240 tons of such mixed soil, 48 tons of cement, 72 tons of yellow sand, and 120 tons of stones.

3. If there are 21 tons of three materials, when all the yellow sand is used up, there are still 7 tons of water left, and 14 tons of stones are needed.

1 Cement: sand: gravel = 2:3:5

2,:cement: multiplied by 240=48;Yellow sand: multiply by 240 = 72;Ishinchiko: multiply by 240=120;

3.: Cement: 21-21 3*2=7;Stones: 21 3*5-21=14;

1 Cement: sand: gravel = 2:3:5

2. 480 tons of cement, 720 tons of yellow sand, and 1,200 tons of stones.

3. 7 tons of cement left. 14 tonnes of stones.

It says that there are 21 tons, and the yellow sand and so on are 21 tons, 21 tons, and 21 tons, and you should say how many tons of stones have increased!!

Kill yourself and catch your own business.

Who's out of this essay question, so difficult!

Let the number B be "1'', then the number of A is , and B is a few percent less than A is [A-B] A. than"Who"Divide by "who".

The number of A is more than the number of B: (The number B is less than the number of A: (

The proportion of the difference in the number of A = (

Let the number B be "1'', then the number of A is , and B is a few percent less than A is [A-B] A. than"Who"Divide by "who".

Let the number B be 1, because the number A is a multiple of the number B, so the number A is.

Less = (Ask if you have a question.)

A = B A = 5 4 B.

Let B be 4a, then A 5a

A-B) A=A5A=

20% less

Logic??? Can't be mentally retarded??? What IQ ???

Let be: B=x so A=

So: (Final answer.)

You guess there is very little hope in asking, you can ask the person who studied with her at the time, even if you only have one here, you can also ask them one by one, after all, the world is sometimes very small.

Thank you for the trouble to adopt!