Answer:
a) The attached pictures show the line number and the plot of the numbers.
b) The opposite of a number is the same distance from zero in the opposite way.
Explanation:
The attached pictures show the number line with the three numbers and their respective opposites.
To find the opposite of a number, we need to find the number of places on the scale from zero. Then, we count the same number of places from zero in the opposite way.