at will be the beat frequency heard when two guitar strings, initially tuned to the same frequency of 298 Hz, are played together after the tension in one string is decreased by 3.0%? [Hint: $f^{\prime}=\frac{1}{\lambda}\sqrt{\frac{F_{T}^{\prime}}{\frac{m}{L}}}$ ], where $f^{\prime }$ is the new frequency, and $F_T^{\prime }$ is the new tension.

• A. 1.3 Hz
• B. 3.4 Hz
• C. 4.5 Hz
• D. 6.8 Hz