If earth rotates at about 1000 mph and it rotates constantly each day. How many rotations will it complete after 4th hour, 8th hour and 24th hour.
So in 1 day, the earth rotates 24,000 miles (according to your data)
after 4 hours it rotated 4000 miles
4000/24000 = 1/6
1/6 of a rotation after 4 hours
do the others in the same way