#include <bits/stdc++.h>

#define VARNAME(x) #x
#define show(x) cerr << #x << " = " << x << endl

using namespace std;
using ll = long long;
using ld = long double;
template <typename T>
vector<T> Vec(int n, T v)
{
    return vector<T>(n, v);
}
template <class... Args>
auto Vec(int n, Args... args)
{
    auto val = Vec(args...);
    return vector<decltype(val)>(n, move(val));
}

template <typename T>
ostream& operator<<(ostream& os, const vector<T>& v)
{
    os << "sz:" << v.size() << "\n[";
    for (const auto& p : v) {
        os << p << ",";
    }
    os << "]\n";
    return os;
}

template <typename S, typename T>
ostream& operator<<(ostream& os, const pair<S, T>& p)
{
    os << "(" << p.first << "," << p.second
       << ")";
    return os;
}


constexpr ll MOD = (ll)1e9 + 7LL;
constexpr ld PI = static_cast<ld>(3.1415926535898);

template <typename T>
constexpr T INF = numeric_limits<T>::max() / 10;

struct Matrix {
    Matrix(const int N) : N(N), table(N, vector<ld>(N, 0)) {}
    const int N;
    const vector<ld>& operator[](const int m) const
    {
        return table[m];
    }
    vector<ld>& operator[](const int m)
    {
        return table[m];
    }
    Matrix operator*(const Matrix& mat) const
    {
        Matrix ans(N);
        for (int i = 0; i < N; i++) {
            for (int j = 0; j < N; j++) {
                for (int k = 0; k < N; k++) {
                    ans[i][j] += table[i][k] * mat[k][j];
                }
            }
        }
        return ans;
    }
    static Matrix Unit(const int N)
    {
        Matrix mat(N);
        for (int i = 0; i < N; i++) {
            mat[i][i] = 1;
        }
        return mat;
    }
    vector<vector<ld>> table;
};

Matrix power(const Matrix& mat, const ll n)
{
    if (n == 0) {
        return Matrix::Unit(mat.N);
    }
    if (n % 2 == 1) {
        return power(mat, n - 1) * mat;
    } else {
        const auto pp = power(mat, n / 2);
        return pp * pp;
    }
}

int main()
{
    cin.tie(0);
    ios::sync_with_stdio(false);
    int R, C;
    ll T;
    cin >> R >> C >> T;
    int sx, sy, gx, gy;
    cin >> sy >> sx >> gy >> gx;
    const int S = sx + sy * C;
    const int G = gx + gy * C;
    const int N = R * C;
    Matrix mat(N);
    vector<vector<bool>> ok(R, vector<bool>(C, true));
    for (int i = 0; i < R; i++) {
        string s;
        cin >> s;
        for (int j = 0; j < C; j++) {
            ok[i][j] = s[j] == '.';
        }
    }
    constexpr int dir[] = {-1, 0, 1, 0, -1};
    for (int i = 0; i < N; i++) {
        const int y = i / C;
        const int x = i % C;
        if (not ok[y][x]) {
            mat[i][i] = 1;
            continue;
        }
        vector<int> nei;
        for (int d = 0; d < 4; d++) {
            const int newy = y + dir[d];
            const int newx = x + dir[d + 1];
            if (newy >= 0 and newy < R and newx >= 0 and newx < C and ok[newy][newx]) {
                nei.push_back(newy * C + newx);
            }
        }
        if (nei.empty()) {
            mat[i][i] = 1;
        } else {
            const ld p = 1.0 / nei.size();
            for (const int e : nei) {
                mat[i][e] = p;
            }
        }
    }
    const Matrix ans = power(mat, T);
    cout << fixed << setprecision(15) << ans[S][G] << endl;

    return 0;
}