1. +4
2. -5
3. (+ 6) + (- 4) = + 2
4. (-5)+(-1)=-6
5. (+8)+(-6)=+2
6. (-4)+(+3)=-1

(a) correct
(b)correct
(c)correct
(d)Incorrect; the correct is (- 6) + (- 2) = - 8
(e)correct
(f)correct
(g)ncorrect; the correct is (+ 7) + (- 10) = - 3

1

No, there are no such integers, which are less than - 3 and greater than -1.

Firstly, draw a number line.

Let +1 be an integer and its additive inverse is -1. From the number line, we see that +1 is 2 more than its additive inverse. So, we reject this integer.
Again, let +2 be an integer, its additive inverse is -2. From the number line, we see that +2 is 4 more than its additive inverse.
Hence, the required integer is 2.

Let the six integers be 1, 2, -2, 3, -3 and 6.
Now, sum of the above integers
= 1+ 2 + (-2) + 3 + (-3) + 6
We can arrange the numbers, so that the positive integers and the negative integers are grouped together.
We have, 1+ 2 + 3 + 6 + (-2) + (-3) = 12 - 2 - 3 = 12 - 5 = 7 
Hence, required integers are 1, 2, -2, 3, -3 and 6.
Note There are infinite combinations exist.

Temperature at 7 : 00 am = + 6° C
It is given that, temperature increased by 4°C in first hour.
So, temperature at 8 : 00 am = +6°C + 4°C  = 10°C
Temperature decreased in second hour by 1°C.
So, the temperature at 9 : 00 am = 10°C - 1°C = 9°C

(a) Now, from the figure, it is clear that +8 is on point D, then forgetting - 8, we should move below to O. After moving 8 steps below 0, we reach at point F So, point F represents - 8.
(b) We know that, points lie above zero are positive integers and lie below zero are negative integers. Here, we see that point G lies below zero. So, G is a negative integer.
(c) On the given number line, point B lies above zero and point E lies below zero. So, it is clear that point B is a positive integer and point E is a negative integer. Now, counting from 0, the distance of B = +4 units, because it is on right of zero and counting from 0, the distance of E = -10 units because it is on left of zero.
∴ Integer B = + 4 and integer E = -10
(d) Here, we see that the distance of point E is far from 0 and below from 0 and we know that on vertical number line below from 0 the value of integers are negative. Hence, point E has the least value.
(e) We know that, on a number line the number decreases as we move to left. Here, vertical number line is given to us, so the number decreases as we move to down. So, decreasing order of values of all points is given here.  D, C, B, A, O, H, G, F, E

(i) We have,  \(0\ \Box -8\)
Since, 0 is to the right of - 8. ∴ 0 > -8
(ii) We have,  \(-1\ \Box\ -15\)
Since, - 1 is to the right of - 15. ∴ -1 > -15
(iii) We have, \(5\ \Box\ -5\)
Since, 5 is to the right of - 5. ∴ 5> -5
(iv)We have, \(11\ \Box\ 15\)
Since, 11 is to the left of 15. ∴ 11 < 15
(v) We have, \(0\ \Box\ 6\)
Since, 0 is to the left of 6.  \(\therefore\) 0 < 6
(vi) We have,  \(-20\ \Box\ 2\) 
Since, - 20 is to the left of 2. \(\therefore\) -20 < 2
Yes, I agree with Rohini. Some examples are as follow:
(a) Every positive integer is larger than every negative integer. e. g. 5 > - 2.
(b) Zero is less than every positive integer. e. g. 0 < 3.
(c) Zero is larger than every negative integer. e. g. 0 > - 4.
(d) Zero is neither a negative integer nor a positive integer, because 0 has neither '+' sign nor '-' sign.
(e) Farther a number from zero, on the right side, larger is its value, because on number line, every integer on the right from zero is greater than zero. e. g. 5 > 0.
(f) Farther a number from zero, on the left side, smaller is its value because on number line, every integer on the left from zero is smaller than zero. e. g. - 8

Draw a line and mark some points at equal distance on it as shown in the figure given below. Mark a point on it as zero. Points to the right of zero are positive integers and marked by +1, + 2, +3 erc., or simply 1, 2, 3 etc and points to the left of zero are negative integers and marked by -1, - 2, - 3 etc. Now, - 3 is a negative integer (since, - 3 has negative sign). So, move 3 points to the left of zero and represent it by point C. 7 is a positive integer (since + 7 has positive sign). So, move 7 points to the right of zero and represent it by point F. To mark - 4 on this line, move 4 points to the left of zero and represent it by point B. To mark - 8, on this line, move 8 points to the left of zero and represent it by point A. To mark - 1 on this line, move 1 point to the left of zero and represent it by point D. To mark 3 on this line, move 3 points to the right of zero and represent it by point E. Thus, we get the following representation of these integers on the number line: