import sys
input = sys.stdin.readline

def Matprod(A, B, N):
    temp = [0] * N*N
    for i in range(N):
        for j in range(N):
            ij = i * N + j
            for k in range(N):
                temp[ij] += A[i*N+k] * B[k*N+j]
    return temp

def Matpow_Linear(A, M, N):
    Mat = [0] * N*N
    for i in range(N):
        Mat[i*N+i] = 1
         
    while M:
        if M & 1:
            Mat = Matprod(Mat, A, N)
        A = Matprod(A, A, N)
        M >>= 1
    return Mat  

H, W, T = map(int, input().split())
sx, sy = map(int, input().split())
gx, gy = map(int, input().split())
N = H * W
M = [0] * N * N
B = []
for i in range(H):
    B.extend(list(input().rstrip()))

dx = [-1, 0, 1, 0]
dy = [0, -1, 0, 1]

def f(h, w):
    return h * W + w

for i in range(H):
    for j in range(W):
        v = f(i,j)
        if B[v] == "#":
            continue
        cnt = 0
        for k in range(4):
            x = i + dx[k]
            y = j + dy[k]
            if B[f(x,y)] == "#":
                continue
            cnt += 1
        if cnt == 0:
            M[v * N + v] = 1
        else:
            for k in range(4):
                x = i + dx[k]
                y = j + dy[k]
                if B[f(x,y)] == "#":
                    continue
                M[f(x,y) * N + v] += 1 / cnt

M = Matpow_Linear(M, T, N)
print(M[f(gx, gy) * N + f(sx, sy)])