①0-(+2)=2

②0-(-2)=2

③(+5)-0=-5

④0-(-3)=3

2. The following calculation is correct (A)

A.(-8)+(-3)=- 1 1

B.(-2)+(+6)=8

C.(-3)-(-6)=-3

D.3-(-5)=-2

3. The two points on the number axis-10 1 and -809 are A and B respectively, and the distance between the two points is (A).

708 C.908 D.7 10

4. Although the price of a stock is 12 yuan, it fell by 1.0 yuan in the morning and rose by 0.2 in the afternoon, so the closing price of this stock on this day is (C).

A.0.2 yuan B.9.8 yuan C. 1 1.2 yuan D. 12 yuan.

5. The sum of all integers whose absolute value is not greater than 4 is (c)

a . 10 b .- 10 c . 0d . 12

6. Let A be the smallest natural number, B be the largest negative integer, and C be the smallest absolute rational number, then a-b+c=( B).

A.- 1 B. 1 C.0 D.2

7. The average temperature of Saturn's surface at night is-150℃, which is 27℃ higher than that at night, so the average temperature of Saturn's surface during the day is _- 123_℃.

8. One day, Xiaoming was running on an east-west expressway. He starts from point A and records his movement relative to point A every 10 minutes (the east is the positive direction, in meters):-1000,100,-978,65438. How far is it from a place? How many meters did he run?

- 1000+ 1 100-978+ 100 1-825+945=243

He is 243 meters east of point a.

1000+ 1 100+978+ 100 1+825+945=5849

He ran 5849 meters at a time.

9. Given that |a|= 1 and |b|=2, the signs of a and b are different, find the value of a+b..

If a= 1 b=-2 a+b=- 1.

If a=- 1 b=2 a+b= 1.