[5] No slope (or a slope of 0)
There is no incline or decline to the line, so there is no slope.
[6] 1
We can use "rise over run" since we have clear points on the graph. See attached.
[7] Undefined slope
This slope of this line is undefined. The formula for slope is [tex]\frac{\text{change in y}}{\text{change in x}}[/tex] which becomes [tex]\frac{0}{0}[/tex] in a case like this. You cannot divide by 0, giving a slope of undefined.
