[填空题]
Suppose a star the size of our Sun, b: q7 v6v6n pe4,wipfs tzpwi24ut with mpkfjex- 2v :n1r 8s+mbass 8.0 times as great, were rotating at a speed of 1.0 revolution every 12 days. If it were to undergo gravitational collapse to a neutron star vfsx8bj 1pn2re-+ :mk 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. $\times10^{9 }$ $rev/day$