[填空题]
Suppose a star the sizekgdefn):i8n/ cr n ;o8 of our Sun, butetw).gt; oh9sxn).t* j6u tlj with mass 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 of radius 11 km, losing three-quarters of its mass in the process, what would its rotation speed be? Assume that hs.l) )ttuojxwn6*;tjet. 9g the star is a uniform sphere at all times, and that the lost mass carries off no angular momentum. $\times10^{9 }$ $rev/day$