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

#define DEBUG(x) cout<<#x<<": "<<x<<endl;
#define DEBUG_VEC(v) cout<<#v<<":";for(int i=0;i<v.size();i++) cout<<" "<<v[i]; cout<<endl

typedef long long ll;
#define vi vector<int>
#define vl vector<ll>
#define vii vector< vector<int> >
#define vll vector< vector<ll> >
#define vs vector<string>
#define pii pair<int,int>
#define pis pair<int,string>
#define psi pair<string,int>
#define pll pair<ll,ll>
#define fi first
#define se second
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define rep1(i,n) for(int i=1;i<=(int)(n);i++)
#define all(c) c.begin(),c.end()
const int inf = 1000000001;
const ll INF = 2e18;
#define MOD 1000000007
#define mod 1000000009
#define pi 3.14159265358979323846
#define Sp(p) cout<<setprecision(15)<< fixed<<p<<endl;
int dx[4] = { 1,0,-1,0 }, dy[4] = { 0,1,0,-1 };
int dx2[8] = { 1,1,0,-1,-1,-1,0,1 }, dy2[8] = { 0,1,1,1,0,-1,-1,-1 };


typedef vector<double> vec;
typedef vector<vec> mat;

mat mul(mat &A, mat &B) {
	mat C(A.size(), vec(B[0].size()));
	for (int i = 0; i < A.size(); i++) {
		for (int k = 0; k < B.size(); k++) {
			for (int j = 0; j < B[0].size(); j++) {
				C[i][j] = C[i][j] + A[i][k] * B[k][j];
			}
		}
	}
	return C;
}


mat pow(mat A, ll n) {
	mat B(A.size(), vec(A.size()));
	for (int i = 0; i < A.size(); i++) {
		B[i][i] = 1;
	}
	while (n > 0) {
		if (n & 1)B = mul(B, A);
		A = mul(A, A);
		n >>= 1;
	}
	return B;
}

int main() {
	int r, c, t;
	cin >> r >> c >> t;
	int si, sj, gi, gj;
	cin >> si >> sj >> gi >> gj;
	vector<vector<char> > b(r, vector<char>(c));
	rep(i, r) {
		rep(j, c) {
			cin >> b[i][j];
		}
	}
	mat a(r*c,vec(1, 0));
	a[si * c + sj][0] = 1.0;
	mat A(r * c, vec(r * c));
	rep(i, r) {
		rep(j, c) {
			if (b[i][j] == '#') {
				continue;
			}
			int k = i*c + j;
			int cnt = 0;
			rep(l, 4) {
				if (b[i + dy[l]][j + dx[l]] == '.') {
					cnt++;
				}
			}
			if (cnt == 0) {
				A[k][k] = 1;
				continue;
			}
			rep(l, 4) {
				if (b[i + dy[l]][j + dx[l]] == '.') {
					int nex = (i + dy[l])*c + (j + dx[l]);
					A[nex][k] = 1.0 / cnt;
				}
			}
		}
	}
	mat B = pow(A, t);
	mat ans = mul(B, a);
	Sp(ans[gi*c + gj][0]);
}