#include "bits/stdc++.h"
using namespace std;
#define int long long
#define FOR(i, a, b) for(int i=(a);i<(b);i++)
#define RFOR(i, a, b) for(int i=(b-1);i>=(a);i--)
#define REP(i, n) for(int i=0; i<(n); i++)
#define RREP(i, n) for(int i=(n-1); i>=0; i--)
#define REP1(i, n) for(int i=1; i<=(n); i++)
#define RREP1(i, n) for(int i=(n); i>=1; i--)
#define ALL(a) (a).begin(),(a).end()
#define UNIQUE_SORT(l) sort(ALL(l)); l.erase(unique(ALL(l)), l.end());
#define CONTAIN(a, b) find(ALL(a), (b)) != (a).end()
#define out(...) printf(__VA_ARGS__)
#if DEBUG
#define debug(...) printf(__VA_ARGS__)
#else
#define debug(...) /* ... */
#endif
template<class T>bool chmax(T &a,const T &b){if(a<b){a=b;return true;}return false;}
template<class T>bool chmin(T &a,const T &b){if(b<a){a=b;return true;}return false;}

void solve();
signed main()
{
#if DEBUG
    std::ifstream in("input.txt");
    std::cin.rdbuf(in.rdbuf());
#endif
    cin.tie(0);
    ios::sync_with_stdio(false);
    solve();
    return 0;
}

/*================================*/
#if DEBUG
#define SIZE 10
#else
#define SIZE 20
#endif

int R,C,T;
int S[2],G[2];
double P[2][SIZE][SIZE];
int CNT[SIZE][SIZE];
string M[SIZE];
int dxy[] = {0,1,0,-1,0};

void solve() {
    cin>>R>>C>>T;
    REP(i,2)cin>>S[i];
    REP(i,2)cin>>G[i];
    REP(i,R)cin>>M[i];
    REP(r,R)REP(c,C) {
        CNT[r][c]=0;
        REP(j,4) {
            int nr = r + dxy[j], nc = c + dxy[j+1];
            if (nr<0||nc<0||nr>=R||nc>=C) continue;
            if (M[nr][nc]=='#') continue;
            CNT[r][c]++;
        }
    }
    REP(i,SIZE)REP(j,SIZE)P[0][i][j]=P[1][i][j]=0;
    P[0][S[0]][S[1]]=1;
    REP(i,min(10000LL,T)) {
        int from = i%2, to = (i+1)%2;
        REP(r,R)REP(c,C) P[to][r][c]=0;
        REP(r,R)REP(c,C) {
            if (CNT[r][c]==0) {
                P[to][r][c]=P[from][r][c];
                continue;
            }
            REP(j,4) {
                int nr = r + dxy[j], nc = c + dxy[j+1];
                if (nr<0||nc<0||nr>=R||nc>=C) continue;
                if (M[nr][nc]=='#') continue;
                P[to][nr][nc] += P[from][r][c]/CNT[r][c];
            }
        }
    }
    out("%.10f\n",P[T%2][G[0]][G[1]]);
}