The answer is 4589000.
And the reason, is:
The thousands place is the number 9, so you look at the number next to it on the right side, which is the number 2. Is 2 above 5, or over five? Its below five. So since its below five, the nine will stay as a nine but the rest of the numbers on the right side of the nine will become 0's. But if it was a 5 or above, the nine would become a 10. But you cant say 45810000, so you'd have to change the 8 to a 9.
Hope this helps :)
n 34519, the hundredth digit is 5 and so, rounding off 34519 to the nearest 1000 result in 35000.