A guitar string of mass mm under tension resonates in its fundamental mode outside the ear canal and the string produces resonance in the ear's fundamental mode and so is perceived at maximum loudness. A second guitar string of different mass but of the same length and under the same tension again vibrates in the fundamental mode. The new string is designed to produce a resonance in the next higher harmonic of the ear. What should be the mass of the the new string in terms of the original mass mm