[填空题]
The A string on a violin has a fuo zj+ e09p;p .rrb-),;zmlyhvqpo . fxirz59vndamental frequency of 440 Hz. The length owhlmruc1qm s-x t 4/(v,w ,224vxcwnl f the vibrating portion is 32 cm, and it has a mass-qmvwxm,2cw 4c ,lwu/ 1s4rnx2 (htvl of 0.35 g. Under what tension must the string be placed? N
