Final Answer:
The value for the 'Z-axis' not zero (0) because the surface of the screen is zero (0) on the 'Z-axis', so the correct option is 3.
Step-by-step explanation:
To determine why the value for the 'Z-axis' is or is not zero (0) for the surface of the screen, we need to understand the reference point or origin in a 3D coordinate system.
1. If the back of the screen is zero (0) on the 'Z-axis', this would imply that the 'Z-axis' value increases as we move from the back of the screen to the front.
2. If the zero point for the 'Z-axis' is located in the middle of the device, then the values on the 'Z-axis' would be negative behind this central point and positive in front of it.
3. If the surface of the screen is zero (0) on the 'Z-axis', this suggests that the screen's surface is the reference point for the 'Z-axis', and any point on this surface will indeed have a 'Z-axis' value of zero.
4. If the back of the device is zero (0) on the 'Z-axis', then this would be similar to the first option, where the zero point is behind the screen, and we would expect positive values as we move towards the screen's surface.
Given these options, we deduce that the surface of the screen being zero (0) on the 'Z-axis' means that the 'Z-axis' value for any point on the screen's surface is zero.
Other components of the device will have 'Z-axis' values greater or less than zero depending on their position relative to the screen's surface.
This is a correct statement because in many coordinate systems, especially those used for screens or interfaces, the surface is often treated as the origin on the axis perpendicular to it, which in this case would be the 'Z-axis'.
Therefore, the true statement among the options given is option 3: The surface of the screen is zero (0) on the 'Z-axis'.