[填空题]
Suppose a star the size of our Sun, but with mass 8.0 toq2jxo hx1x 02imes as great, w +eec3*nz s27vfy )wpjere rotating at a speed of 1.0 revolution every 12 days. If it were to 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? Assum + p2y*7zneejcs fwv3)e that the star is a uniform sphere at all times, and that the lost mass carries off no angular momentum. $\times10^{9 }$ $rev/day$