Problem

A stretched string

1.20\,\text{m}

long is fixed at both ends and vibrates in the fourth harmonic. At a point on the string the displacement amplitude is

80\%

of the maximum possible amplitude. Which pair gives the two smallest distances of this point from the left end? a)

0.06\,\text{m}

and

0.24\,\text{m}

0.09\,\text{m}

and

0.21\,\text{m}

0.12\,\text{m}

and

0.18\,\text{m}

0.07\,\text{m}

and

0.17\,\text{m}