[填空题]
The A string on a vio5psq rz s,k:.3r r;o)mnb0 lswli0qye*b0+q ava x r8+qtn has a fundamental frequency of 440 Hz. The length of the vibrating portion is 32 cm, and it has a mass of 00 a8r*x+0q ybteqqv a+.35 g. Under what tension must the string be placed? N