[填空题]
Suppose a star the size of our Sun, but with mass 8.0 tim ik8 zfiywmx605g8l2j es ao;+sr4lty-zyhf: (qdk .0tcmo93s kss great, were rotating at a speed of 1.0 revolution every 12 days. If it were to;ts 0zoyms dq4kycr -.:9ok(t sf3 hl+ undergo gravitational collapse to a neutron 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. $\times10^{9 }$ $rev/day$