[问答题]
A block of mass m is wjr rzmk /e)y0t3kx3,supported by two identical parallel vertical springs, ez6jaqq u5/4bhi p nd3nxbz x:a,j(ix2q; gv 96ach with spring stiffness constant k (Fig. 11–49). What w b:j p9zid3zxx2 q(5jaqnhi xau;4bv 6,nqg6/ ill be the frequency of vibration?