144 cubic inch
Step-by-step explanation:
Angle 8 = 60°
Step-by-step explanation:
See the attached diagram.
The measurement of angle 2 is 60°.
Now, angle 2 = angle 4 as they are equal vertically opposite angles.
Hence, angle 4 = 60°
Now, horizontal lines AB ║ CD and the inclined line is the transverse line.
Hence, angle 4 and angle 8 are corresponding angles.
Therefore, angle 4 = angle 8 = 60° (Answer)