*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 frequency of 3.550 MHz, we can use the following formula:

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

where:
- $L$ = length of the dipole in feet
- $f$ = frequency in MHz

### Calculation:
1. Substitute the frequency into the formula:
   - $f = 3.550$ MHz
   - Thus, 

$$
L = \frac{468}{3.550} \approx 132 \text{ feet}
$$

This calculation shows that the correct answer is **132 feet**.

### Explanation of Choices:
- **A: 42 feet**  
  This length is too short for a 1/2 wave dipole at 3.550 MHz. It would be more appropriate for a much higher frequency.

- **B: 84 feet**  
  This length is also too short. It might be suitable for a frequency around 7.1 MHz, which is not the frequency in question.

- **C: 132 feet**  
  This is the correct answer, as shown in the calculation above.

- **D: 263 feet**  
  This length is too long for 3.550 MHz. It would be more appropriate for a much lower frequency, around 1.4 MHz.

### Summary:
- The correct length for a 1/2 wave dipole antenna at 3.550 MHz is approximately **132 feet**.
- The formula $L = \frac{468}{f}$ is a useful rule of thumb for calculating dipole lengths in feet based on frequency in MHz.