import std.conv, std.functional, std.stdio, std.string;
import std.algorithm, std.array, std.bigint, std.complex, std.container, std.math, std.numeric, std.range, std.regex, std.typecons;
import core.bitop;

class EOFException : Throwable { this() { super("EOF"); } }
string[] tokens;
string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; }
int readInt() { return readToken.to!int; }
long readLong() { return readToken.to!long; }
real readReal() { return readToken.to!real; }

bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } }
bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } }

int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1; (unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; }
int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); }
int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); }


int M, N, T;
int SX, SY;
int TX, TY;
string[] B;

int V;

real[][] mul(in real[][] a, in real[][] b) {
  auto c = new real[][](V, V);
  foreach (u; 0 .. V) {
    c[u][] = 0.0;
  }
  foreach (u; 0 .. V) foreach (w; 0 .. V) foreach (v; 0 .. V) {
    c[u][v] += a[u][w] * b[w][v];
  }
  return c;
}

void main() {
  try {
    for (; ; ) {
      M = readInt();
      N = readInt();
      T = readInt();
      SX = readInt();
      SY = readInt();
      TX = readInt();
      TY = readInt();
      B = new string[M];
      foreach (x; 0 .. M) {
        B[x] = readToken();
      }
      
      V = 0;
      auto ids = new int[][](M, N);
      foreach (x; 0 .. M) foreach (y; 0 .. N) {
        ids[x][y] = -1;
      }
      foreach (x; 0 .. M) foreach (y; 0 .. N) {
        if (B[x][y] == '.') {
          ids[x][y] = V++;
        }
      }
      
      auto a = new real[][](V, V);
      foreach (x; 0 .. M) foreach (y; 0 .. N) {
        if (B[x][y] == '.') {
          const u = ids[x][y];
          a[u][] = 0.0;
          int cnt;
          foreach (dir; 0 .. 4) {
            const xx = x + [+1, 0, -1, 0][dir];
            const yy = y + [0, +1, 0, -1][dir];
            if (B[xx][yy] == '.') {
              const v = ids[xx][yy];
              ++cnt;
              a[u][v] += 1.0;
            }
          }
          if (cnt == 0) {
            a[u][u] = 1.0;
          } else {
            a[u][] /= cnt;
          }
        }
      }
      
      auto x = a;
      auto y = new real[][](V, V);
      foreach (u; 0 .. V) foreach (v; 0 .. V) {
        y[u][v] = (u == v) ? 1.0 : 0.0;
      }
      for (long e = T; e; e >>= 1) {
        if (e & 1) {
          y = mul(y, x);
        }
        x = mul(x, x);
      }
      writefln("%.10f", y[ids[SX][SY]][ids[TX][TY]]);
    }
  } catch (EOFException e) {
  }
}