[填空题]
A 75-cm-long guitar strinoxd/36dn dh7h g op k d9b5vwve*4f mass 2.10 g is near a tube that is open at one end and also 75 cm long. How much tension should be in the string if it is to produce resonance (in its fundamental mode) with the third 5p*w9 k bv4evdharmonic in the tube? $ \times10^{ 2}$ N
