Answer:
Option 2.
Explanation:
Let as consider x be the air conditioning unit's actual capacity and y is the maximum variance in British thermal units (Btu).
It is given that an air conditioning unit promises to have a cooling capacity of 6,000 British thermal units (Btu).
We need to find the graph that could be used to determine the variance levels that would cause a unit to be rejected because of its cooling capacity.
It means the maximum variance is less than or equal to absolute difference of actual capacity and 6,000.

The related equation of this inequality is

It is a V-shaped curve with vertex (6000,0) and y-intercept (0,6000).
The related curve is a solid V-shaped curve because the points on curve included in the solution set.
The shaded region lie below the curve because the sign of inequality is ≤.
Therefore the correct option is 2.