[填空题]
Suppose a star the sc*1xs ph 7kmp(z5s m,9 .kjq4cs 13igdhahfn 2k5 jgt(n/ohh: ize of our Sun, but 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 hjotg5(/n k:h 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. $\times10^{9 }$ $rev/day$