Two Taut Strings of Identical Mass and Length Are Stretched

Multiple Choice

Two taut strings of identical mass and length are stretched with their ends fixed,but the tension in one string is 1.10 times greater than in the other.Waves on the string with the lower tension propagate at 35.2 m/s.The fundamental frequency of that string is 258 Hz.What is the beat frequency when each string is vibrating at its fundamental frequency?

A) 11.0 Hz
B) 9.00 Hz
C) 13.7 Hz
D) 12.6 Hz
E) 17.1 Hz