[填空题]
Suppose a star the size hjbt*fse6 :9md7*9/ uh yaiw)t:ojqtof our Su7 szl20plvrr1n, 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 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 2r7lz 0vs1plroff no angular momentum. $\times10^{9 }$ $rev/day$