Question: solve it complete part $a$ and $b$ with the line segment bearing azm back azimuth angle
1. **Stating the problem:**
We need to solve parts $a$ and $b$ involving a line segment's bearing, azimuth, and back azimuth angles.
2. **Understanding the terms:**
- The **bearing** is the direction of a line segment measured clockwise from the north.
- The **azimuth** is the angle measured clockwise from the north direction to the line segment.
- The **back azimuth** is the azimuth of the line segment in the opposite direction, which is the azimuth plus or minus $180^\circ$.
3. **Formula for back azimuth:**
$$\text{Back Azimuth} = \begin{cases} \text{Azimuth} + 180^\circ, & \text{if Azimuth} < 180^\circ \\ \text{Azimuth} - 180^\circ, & \text{if Azimuth} \geq 180^\circ \end{cases}$$
4. **Part a: Calculate the azimuth and bearing of the line segment.**
- Suppose the line segment has coordinates or directions given (not specified in the prompt).
- The azimuth is measured clockwise from north.
- The bearing is expressed as $N$ or $S$ followed by the angle east or west.
5. **Part b: Calculate the back azimuth.**
- Use the formula above to find the back azimuth.
6. **Example (assuming azimuth $120^\circ$):**
- Back azimuth $= 120^\circ + 180^\circ = 300^\circ$
7. **Summary:**
- Bearing and azimuth describe the direction of a line segment.
- Back azimuth is the opposite direction, found by adding or subtracting $180^\circ$.
Since no specific values or coordinates were provided, this is the general method to solve parts $a$ and $b$.