*Question T0C06:
Which of the following is an acceptable method to determine whether your station complies with FCC RF exposure regulations?*  

*Correct Answer is  D: All these choices are correct*  

### AI Response: (may contain errors)  

To determine whether your station complies with FCC RF exposure regulations, the correct answer is:

**D: All these choices are correct.**

### Explanation:

1. **Why the correct answer is correct:**
   - All methods listed (A, B, and C) are valid approaches to assess RF exposure:
     - **A: By calculation based on FCC OET Bulletin 65**: This bulletin provides guidelines for evaluating RF exposure using mathematical calculations based on the power output and frequency of the transmitter.
     - **B: By calculation based on computer modeling**: Computer modeling can simulate RF exposure scenarios, allowing for a detailed analysis of how RF energy propagates in the environment.
     - **C: By measurement of field strength using calibrated equipment**: Direct measurement of RF field strength with calibrated equipment provides empirical data to assess compliance with exposure limits.

2. **Why the other choices are incorrect:**
   - There are no incorrect choices in this case, as all methods are acceptable. Each method has its own advantages and can be used depending on the specific circumstances of the station and the available resources.

### Useful Formulas and Rules of Thumb:
- **Power Density Calculation**: To calculate the power density ($S$) at a distance ($d$) from a point source, you can use the formula:
  
  $$
  S = \frac{P_T \times G}{4 \pi d^2}
  $$

  where:
  - $S$ = power density in watts per square meter (W/m²)
  - $P_T$ = transmitter power in watts (W)
  - $G$ = gain of the antenna (linear)
  - $d$ = distance from the antenna in meters (m)

- **Exposure Limits**: Familiarize yourself with the specific exposure limits set by the FCC, which vary based on frequency and duration of exposure.

By understanding these methods and calculations, you can effectively evaluate your station's compliance with RF exposure regulations.