#!/usr/bin/env python3
# %%
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
import numpy as np

# %%
R, C, T = map(int, readline().split())
Sy, Sx = map(int, readline().split())
Gy, Gx = map(int, readline().split())
B = ''.join(read().decode().split())

# %%
N = R * C
graph = [[] for _ in range(N)]
mat = np.zeros((N,N))
for i in range(N):
    if B[i] == '#':
        continue
    deg = 0
    for dx in [1, -1, -C, C]:
        if B[i + dx] == '.':
            deg += 1
    if deg == 0:
        mat[i, i] = 1.0
    else:
        p = 1 / deg
        for dx in [1, -1, -C, C]:
            if B[i + dx] == '.':
                mat[i, i + dx] = 1 / deg
        


# %%
A = np.linalg.matrix_power(mat, T)
S = Sy * C + Sx
G = Gy * C + Gx
print(A[S,G])