Karst is a topography formed from the dissolution of soluble rocks such as limestone, dolomite, and gypsum. It is characterized by underground drainage systems with sinkholes and caves. It has also been documented for more weathering- resistant rocks, such as quartzite, given the right conditions.
A magnet has a South Pole and a North Pole. South Pole and South Pole can't connect to her other, same as North and North. The same poles push each other away.
South Pole and North Pole connect.
Data:

n (Wave node)
V (Wave belly)
L (Wave length)
<span>The number of bells is equal to the number of the harmonic emitted by the string.
</span>

Wire 2 → 2º Harmonic → n = 2







Wire 1 → 1º Harmonic or Fundamental rope → n = 1



If, We have:
V = 42L
Soon:



Answer:
<span>The fundamental frequency of the string:
</span>
21 Hz