#include <cstdio>
#include <iostream>
#include <string>
#include <sstream>
#include <stack>
#include <algorithm>
#include <cmath>
#include <queue>
#include <map>
#include <set>
#include <cstdlib>
#include <bitset>
#include <tuple>
#include <assert.h>
#include <deque>
#include <bitset>
#include <iomanip>
#include <limits>
#include <chrono>
#include <random>
#include <array>
#include <unordered_map>
#include <functional>
#include <complex>
#include <numeric>
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
//constexpr long long MAX = 5100000;
constexpr long long INF = 1LL << 60;
constexpr int inf = 1000000007;
constexpr long long mod = 1000000007LL;
//constexpr long long mod = 998244353LL;
const long double PI = acos((long double)(-1));

using namespace std;
typedef unsigned long long ull;
typedef long long ll;
typedef long double ld;


template< class T >
struct Matrix {
    vector< vector< T > > A;

    Matrix() {}

    Matrix(size_t n, size_t m) : A(n, vector< T >(m, 0)) {}

    Matrix(size_t n) : A(n, vector< T >(n, 0)) {};

    size_t height() const {
        return (A.size());
    }

    size_t width() const {
        return (A[0].size());
    }

    inline const vector< T >& operator[](int k) const {
        return (A.at(k));
    }

    inline vector< T >& operator[](int k) {
        return (A.at(k));
    }

    static Matrix I(size_t n) {
        Matrix mat(n);
        for (int i = 0; i < n; i++) mat[i][i] = 1;
        return (mat);
    }

    Matrix& operator+=(const Matrix& B) {
        size_t n = height(), m = width();
        assert(n == B.height() && m == B.width());
        for (int i = 0; i < n; i++)
            for (int j = 0; j < m; j++)
                (*this)[i][j] += B[i][j];
        return (*this);
    }

    Matrix& operator-=(const Matrix& B) {
        size_t n = height(), m = width();
        assert(n == B.height() && m == B.width());
        for (int i = 0; i < n; i++)
            for (int j = 0; j < m; j++)
                (*this)[i][j] -= B[i][j];
        return (*this);
    }

    Matrix& operator*=(const Matrix& B) {
        size_t n = height(), m = B.width(), p = width();
        assert(p == B.height());
        vector< vector< T > > C(n, vector< T >(m, 0));
        for (int i = 0; i < n; i++)
            for (int j = 0; j < m; j++)
                for (int k = 0; k < p; k++)
                    C[i][j] = (C[i][j] + (*this)[i][k] * B[k][j]);

        
        //正規化
        for (int j = 0; j < m; j++) {
            T all = 0;
            for (int i = 0; i < n; i++) {
                all += C[i][j];
            }
            if (all > 0.5) {
                for (int i = 0; i < n; i++) {
                    C[i][j] /= all;
                }
            }
        }
        
        A.swap(C);
        return (*this);
    }

    Matrix& operator^=(long long k) {
        Matrix B = Matrix::I(height());
        while (k > 0) {
            if (k & 1) B *= *this;
            *this *= *this;
            k >>= 1LL;
        }
        A.swap(B.A);
        return (*this);
    }

    Matrix operator+(const Matrix& B) const {
        return (Matrix(*this) += B);
    }

    Matrix operator-(const Matrix& B) const {
        return (Matrix(*this) -= B);
    }

    Matrix operator*(const Matrix& B) const {
        return (Matrix(*this) *= B);
    }

    Matrix operator^(const long long k) const {
        return (Matrix(*this) ^= k);
    }

    friend ostream& operator<<(ostream& os, Matrix& p) {
        size_t n = p.height(), m = p.width();
        for (int i = 0; i < n; i++) {
            os << "[";
            for (int j = 0; j < m; j++) {
                os << p[i][j] << (j + 1 == m ? "]\n" : ",");
            }
        }
        return (os);
    }


    T determinant() {
        Matrix B(*this);
        assert(width() == height());
        T ret = 1;
        for (int i = 0; i < width(); i++) {
            int idx = -1;
            for (int j = i; j < width(); j++) {
                if (B[j][i] != 0) idx = j;
            }
            if (idx == -1) return (0);
            if (i != idx) {
                ret *= -1;
                swap(B[i], B[idx]);
            }
            ret *= B[i][i];
            T vv = B[i][i];
            for (int j = 0; j < width(); j++) {
                B[i][j] /= vv;
            }
            for (int j = i + 1; j < width(); j++) {
                T a = B[j][i];
                for (int k = 0; k < width(); k++) {
                    B[j][k] -= B[i][k] * a;
                }
            }
        }
        return (ret);
    }
};

int H, W;
int cnv(int h, int w) {
    return h * W + w;
}

int dh[] = { 1,-1,0,0 };
int dw[] = { 0,0,1,-1 };

using Real = double;
int main()
{
    /*
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    */

    ll T; scanf("%d %d %lld", &H, &W, &T);
    int sh, sw, gh, gw; scanf("%d %d %d %d", &sh, &sw, &gh, &gw);
    sh--; sw--; gh--; gw--;
    vector<string> vs;
    {
        vector<string> tvs(H); for (int i = 0; i < H; i++) cin >> tvs[i];
        vs.resize(H - 2, string(W - 2, ' '));
        for (int i = 1; i < H - 1; i++) for (int j = 1; j < W - 1; j++) vs[i - 1][j - 1] = tvs[i][j];
    }
    H -= 2;
    W -= 2;
    Matrix<Real> mat(H * W);

    for (int i = 0; i < H; i++) {
        for (int j = 0; j < W; j++) {
            if (vs[i][j] == '#') continue;
            int cnt = 0;
            int pos = cnv(i, j);
            for (int k = 0; k < 4; k++) {
                int nh = i + dh[k];
                int nw = j + dw[k];
                if (nh < 0 or nh >= H or nw < 0 or nw >= W) continue;
                if (vs[nh][nw] == '.') cnt++;
            }
            if (cnt == 0) {
                mat[pos][pos] = 1.0;
            }
            else {
                for (int k = 0; k < 4; k++) {
                    int nh = i + dh[k];
                    int nw = j + dw[k];
                    if (nh < 0 or nh >= H or nw < 0 or nw >= W) continue;
                    if (vs[nh][nw] == '.') {
                        int nxt = cnv(nh, nw);
                        mat[nxt][pos] = 1.0 / (Real)cnt;
                    }
                }
            }
        }
    }
    mat ^= T;
    Matrix<Real> ini(H * W, 1); ini[cnv(sh, sw)][0] = 1.0;
    mat *= ini;
    cout << fixed << setprecision(12) << mat[cnv(gh, gw)][0] << endl;
    return 0;
}