Help me with some math problems in the first year of junior high school! Urgent! Urgent!

First of all, you don't need to think too complicated. Question, you might as well think about moving forward and backward like this, you might as well look at it as a car forward and backward, when moving forward, we say it's +x meters (x stands for number), moving backward means it's -x meters, then you can think like this: moving 5 meters backward is -5 meters, then +5 meters is moving forward, then the car is 5 meters backward and 5 meters forward, then it is back to the original point.

The answer is 0 meters Question This is just a question of the dividing line, the length will not change, because 1 meter is its zero cut-off point, for example, the table is long meters, then it is less than 1 meter, this less is the meaning of - So the answer is meters, if the table is long meters then it is longer than one meter, then the answer is 0,6 meters, so this is the same as we take 0 as the zero cut-off point in reality, but the number has changed Question This question seems to have a mistake, really Electrons are negatively charged I have learned like this, the question seems to be wrong I won't solve the question This question is also very simple, it is 7-8=-1, so the answer is -1c. The landlord learns to be serious, these are very simple questions, maybe you are drilling, but the mathematics of the first year of junior high school is very simple, but it is not good to learn if you are not serious. I hope you will work hard to study hard and contribute to the motherland.

1.Moving +5m again is moving forward 5m on the basis of -5m, and the object is in the position before his two moves, and the landlord can try to do an experiment himself.

2.Measure it yourself.

3.The charge of the nucleus is: +1, and the charge of the electron is: -1 is 7 degrees Celsius, after five hours it is 17 o'clock is 3 degrees Celsius, and after another seven hours it is 24 o'clock, which is -1 degrees Celsius at 0:00 the next day.

I've written it very clearly, and I hope you understand.

1. Move forward 5 meters, 0 meters away from the position before moving.

2. The length of the table is recorded.

3. The nucleus of the hydrogen atom is +1 electron-1

7, 12:00 - 5 hours--- 17:00 temperature 7 -4 = 3

17:00--24:00 after seven hours, that is, 0:00 the next day.

Temperature 3 -4 = -1

1.Move forward 5m

3.There is a problem with the question, the nucleus is positively charged, but the electrons are negatively charged, which is the reason why the atom is not charged, common sense error.

1.Forward 5cm; Back to square one. 2.I'm cooling.。。。 7.-1°

1:+5 is moving forward Move 0 meters 2: I don't understand 3: I still don't understand.

1. Solution: (1) 1 10(65 70 85 + 75 + 85 + 79 + 74 + 91 + 81 + 95) 80

Answer: The average monthly use of plastic bags by the families of these 10 students is 80 (2) 80*1000*50%=40000Answer: After the implementation of the "plastic restriction order", it is estimated that the monthly use of plastic bags by 1 000 students' families can be reduced by 40 000

Actually walked 80 meters and his position was at the origin or 0

He walked 80 meters, but the location was still at the beginning of the departure.

og bc, the point o is the intersection of the three angular bisectors of abc, 2=90°- bce=90°-1 2 acb, 1= dab+ dba

1/2(∠bac+∠abc)

1 2 (BAC+ABC+ ACB-ACB) (triangle inner angle and 180°).

90-1/2∠acb=∠2

Because og bc, the point o is the intersection of the three angular bisectors of abc so 2=90°- bce=90°-1 2 acb so 1= dab+ dba

1/2(∠bac+∠abc)

1 2 ( BAC + ABC + ACB - ACB) (triangle inner angle sum) = 90-1 2 ACB = 2