#define _USE_MATH_DEFINES
#include "bits/stdc++.h"
using namespace std;
#define FOR(i,j,k) for(int (i)=(j);(i)<(int)(k);++(i))
#define rep(i,j) FOR(i,0,j)
#define each(x,y) for(auto &(x):(y))
#define mp make_pair
#define MT make_tuple
#define all(x) (x).begin(),(x).end()
#define debug(x) cout<<#x<<": "<<(x)<<endl
#define smax(x,y) (x)=max((x),(y))
#define smin(x,y) (x)=min((x),(y))
#define MEM(x,y) memset((x),(y),sizeof (x))
#define sz(x) (int)(x).size()
#define RT return
#define vv(a,b,c,d) vector<vector<a> >(b,vector<a>(c,d))
#define vvv(a,b,c,d,e) vector<vector<vector<a> > >(b,vv(a,c,d,e))
using ll = long long;
using pii = pair<int, int>;
using vi = vector<int>;
using vll = vector<ll>;

template<class Val>
vector<vector<Val> > mulMat(const vector<vector<Val> > &A, const vector<vector<Val> > &B) {
    auto n = A.size(), m = A[0].size(), p = B[0].size();
    vector<vector<Val> > res(n, vector<Val>(p));
    for (int i = 0; i < n; ++i)for (int j = 0; j < p; ++j) for (int k = 0; k < m; ++k)
        res[i][j] += A[i][k] * B[k][j];
    return res;
}

template<class Val>
vector<vector<Val> > powMat(vector<vector<Val> > A, long long k) {
    auto n = A.size();
    vector<vector<Val> > res(n, vector<Val>(n));
    for (int i = 0; i < n; ++i)res[i][i] = 1;
    while (k) {
        if (k % 2)res = mulMat(res, A);
        k /= 2;
        A = mulMat(A, A);
    }
    return res;
}

const int DY[] = { -1,0,1,0 };
const int DX[] = { 0,1,0,-1 };

int R, C, T, Sy, Sx, Gy, Gx;
string B[10];

int id(int y, int x) {
    return y * C + x;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout << fixed << setprecision(20);

    cin >> R >> C >> T >> Sy >> Sx >> Gy >> Gx;
    rep(y, R)cin >> B[y];

    auto A = vv(double, R*C, R*C, 0);

    rep(y, R)rep(x, C)if (B[y][x] != '#') {
        int cnt = 0;
        rep(i, 4) {
            int ny = y + DY[i], nx = x + DX[i];
            if (B[ny][nx] == '.')cnt++;
        }
        rep(i, 4) {
            int ny = y + DY[i], nx = x + DX[i];
            if (B[ny][nx] == '.') {
                A[id(y, x)][id(ny, nx)] = 1.0 / cnt;
            }
        }
        if (cnt == 0)A[id(y, x)][id(y, x)] = 1;
    }

    A = powMat(A, T);

    cout << A[id(Sy, Sx)][id(Gy, Gx)] << endl;
}