Final answer:
The roll test is the most effective way to identify a heat-damaged disc wheel.
Step-by-step explanation:
When it comes to identifying a heat-damaged disc wheel, the correct option is (c) the roll test. This test involves rolling the wheel on a flat surface and observing for any irregularities or deformations in its shape. Heat damage can cause the wheel to warp or become misshapen, which can be detected through the roll test.
Using a carpenter's square or a ball tape would not be effective in identifying heat-damaged disc wheels, as they are not designed for this purpose. Therefore, (a) a carpenter's square and (b) a ball tape are not the correct options.
The correct answer is (d) all of these since only the roll test can effectively identify a heat-damaged disc wheel.