*Question G9B11:
What is the approximate length for a 1/2 wave dipole antenna cut for 3.550 MHz?*  

*Correct Answer is  C: 132 feet*  

### AI Response: (may contain errors)  

To determine the approximate length of a 1/2 wave dipole antenna for a specific frequency, you can use the formula:

$$
L = \frac{468}{f}
$$

where:
- $L$ is the length of the dipole in feet.
- $f$ is the frequency in megahertz (MHz).

For a frequency of 3.550 MHz, the calculation is:

$$
L = \frac{468}{3.550} \approx 131.83 \text{ feet}
$$

Rounding to the nearest whole number, the length is approximately 132 feet.

### Explanation of Choices:
- **A: 42 feet**  
  This length is too short for a 1/2 wave dipole at 3.550 MHz. It might be closer to a 1/2 wave dipole for a much higher frequency.
  
- **B: 84 feet**  
  This length is also too short for 3.550 MHz. It could be suitable for a higher frequency, but not for the given frequency.
  
- **C: 132 feet**  
  This is the correct length for a 1/2 wave dipole at 3.550 MHz, as calculated above.
  
- **D: 263 feet**  
  This length is too long for a 1/2 wave dipole at 3.550 MHz. It might be closer to a full wave dipole for a lower frequency.

By using the formula and understanding the relationship between frequency and antenna length, you can determine the correct dipole length for any given frequency.