From the figure we see that the function in b, only asigns values for the points in -3, -1, 1, 3 and 4 of the x axis.
Then it's domain is
To find the range of the figure in b, we have to see what values does it take in the y axis, we notice that this values are -4, 0, 1, 4 and 5. Hence
In the case of c. we notice that the lines go on (that's is why it's represented by arrows). We note that if the lines go on, eventually they will take all the values on the x axis. Then
For the range we notice that it will take all the positive values on the y axis. then
In the case of the function a, we notice that the function assigns values to every point from -4 to 4 on the x axis. Then we can conclude that the domain is
We also notice that the values that y takes are from 0 to 4, therefore