Six houses, K, L, M, N, O and P, are located in the same colony. P is 400 m to the west of K. M is 200 m to the east of L. O is 300 m to the north of K. N is 150 m to the south of L. L is 250 m to the south of K. What is the straight distance between O and N?
1
400 m
2
600 m
3
700 m
4
350 m