#include <bits/stdc++.h>
 
using namespace std;

vector <vector<long double>> mul(vector <vector<long double>> a, vector<vector<long double>> b)
{
    int n = a.size();
    int m = a[0].size();
    int k = b[0].size();
    vector <vector<long double>>c(n, vector<long double>(k,0));

    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < k; j++)
        {
            for (int k = 0; k < m; k++)
            {
                c[i][j] += a[i][k]*b[k][j];
            }
        }
    }

    return c;
}

int dy[4] = {-1,0,1,0};
int dx[4] = {0,1,0,-1};
int sy,sx;
int gy,gx;
int r,c,t;
char board[10][10];


int main(void)
{
    cin.tie(0);
    ios::sync_with_stdio(false);

    cin >> r >> c >> t;
    cin >> sy >> sx;
    cin >> gy >> gx;
    for(int i=0;i<r;i++)
    {
        for(int j=0;j<c;j++)
        {
            cin >> board[i][j];
        }
    }

    vector <vector<long double>>a(r*c, vector<long double>(r*c,0));
    vector <vector<long double>>b(r*c, vector<long double>(r*c,0));

    for(int i=0;i<r;i++)
    {
        for(int j=0;j<c;j++)
        {
            if(board[i][j]=='#') continue;
            int cnt = 0;
            for(int k=0;k<4;k++)
            {
                int y = i + dy[k];
                int x = j + dx[k];
                if(y<0 || y>=r || x<0 || x>=c) continue;
                if(board[y][x]!='#')
                {
                    cnt++;
                }
            }
            for(int k=0;k<4;k++)
            {
                int idx1 = i*c + j;
                int y = i + dy[k];
                int x = j + dx[k];
                if(y<0 || y>=r || x<0 || x>=c) continue;
                int idx2 = y*c + x;
                //cout << i << ' ' << j << ' ' << y << ' ' << x << ' ' << (1.0)/cnt << ' ' << idx2 << ' ' << idx1 << '\n';
                a[idx2][idx1] = (1.0/cnt);        
            }
            if(cnt==0)
            {
                if(i==sy && j==sx && gy==sy && gx==sx)
                {
                    cout << "1.0000000000000000" << '\n';
                    return 0;
                }
                a[i*c+j][i*c+j] = 1;
            }
        }
    }

    int s = sy*c + sx;
    int g = gy*c + gx;

    b[s][s] = 1;

    while(t > 0)
    {
        if(t%2==1)
        {
            b = mul(a,b);
        }
        a = mul(a,a);
        t/=2;
    }

    cout << fixed;
    cout.precision(16);

    cout << b[g][s] << '\n';

    return 0;
}