Find the error intervals for the following rounded numbers

Question 1:

8.39 (3 s.f.)

8.385≤x<8.395

Question 2:

1.183 (3 d.p.)

1.1825≤x<1.1835

Question 3:

52.1 (3 s.f.)

52.05≤x<52.15

Question 4:

687 (3 s.f.)

686.5≤x<687.5