[填空题]
Suppose a star the size of our Sun, but with mass 8.0 hc o sjw5 nrxc(b(),j/times as gre3yunyx 7dk+itfg3 )4g at, were rotating at a speed of 1.0 revolution every 12 days. If it were to undergo gravitational collapse to a neug37ix u4dn)+gy ky f3ttron star of radius 11 km, losing three-quarters of its mass in the process, what would its rotation speed be? Assume that the star is a uniform sphere at all times, and that the lost mass carries off no angular momentum. $\times10^{9 }$ $rev/day$