[填空题]
Suppose a star the size of our Sun, but withr;jdzz - c4+ww mass 8.0 times as grh7-+),rpsc mga mcie; eat, were rotating at a speed of 1.0 revolution every 12 days. If it were to undergo gravitational collapse to a neutm s7e-aghir m)c cp;+,ron 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. $\times10^{9 }$ $rev/day$