package yukicoder;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.StringTokenizer;

public class P659 {
	
	static double [][] pow(double[][] A, long n) {
		if(n==1) {
			return A;
		}
		if(n%2==0) {
			double[][] B = pow(A, n/2);
			return mul(B, B);
		} else {
			double[][] B = mul(A, pow(A, n-1));
			return B;
		}
	}
	
	static double[][] mul(double [][] A, double [][] B) {
		assert A[0].length == B.length;
		int n = A.length;
		int k = A[0].length;
		int m = B[0].length;
		double[][] C = new double[n][m];
		for(int i=0; i<n; i++) {
			for(int j=0; j<m; j++) {
				for(int l=0; l<k; l++) {
					C[i][j] = (C[i][j] + A[i][l]*B[l][j]);
				}
			}
		}
		return C;
	}

	static int[][] ds = {{1, 0}, {-1, 0}, {0, 1}, {0, -1}};
	public static void main(String[] args) throws IOException {
		MyScanner sc = new MyScanner(System.in);
		int r = sc.nextInt();
		int c = sc.nextInt();
		int t = sc.nextInt();
		int sy = sc.nextInt();
		int sx = sc.nextInt();
		int gy = sc.nextInt();
		int gx = sc.nextInt();
		char[][] map = new char[r][c];
		for(int i=0; i<r; i++) {
			String s = sc.next();
			for(int j=0; j<c; j++) map[i][j] = s.charAt(j);
		}
		{
			int cnt = 0;
			for(int k=0; k<4; k++) {
				int ny = sy+ds[k][0];
				int nx = sx+ds[k][1];
				if(0<=ny && ny < r && 0<=nx && nx < c && map[ny][nx]=='.') cnt++;
			}
			if(cnt==0 && gx == sx && gy == sy) {
				System.out.println(1);
				return;
			}
			if(cnt==0) {
				System.out.println(0);
				return;
			}
		}
		double[][] A = new double[100][100];
		for(int y=0; y<r; y++) {
			for(int x=0; x<c; x++) {
				int cnt = 0;
				for(int k=0; k<4; k++) {
					int ny = y+ds[k][0];
					int nx = x+ds[k][1];
					if(0<=ny && ny < r && 0<=nx && nx < c && map[ny][nx]=='.') cnt++;
				}
				if(cnt==0) continue;
				int here = r*y+x;
				for(int k=0; k<4; k++) {
					int ny = y+ds[k][0];
					int nx = x+ds[k][1];
					int next = r*ny+nx;
					if(0<=ny && ny < r && 0<=nx && nx < c && map[ny][nx]=='.') A[here][next] = (double)1/(double)cnt;
				}
			}
		}
		System.out.println(pow(A, t)[sy*r+sx][gy*r+gx]);
	}

	static class MyScanner
	{
		BufferedReader br;
		StringTokenizer st;
		public MyScanner(InputStream s)
		{
			br=new BufferedReader(new InputStreamReader(s));
		}
		public String nextLine() throws IOException
		{
			return br.readLine();
		}
		public String next() throws IOException
		{
			while(st==null || !st.hasMoreTokens())
				st=new StringTokenizer(br.readLine());
			return st.nextToken();
		}
		public int nextInt() throws IOException
		{
			return Integer.parseInt(next());
			
		}
		public double nextDouble() throws IOException
		{
			return Double.parseDouble(next());
		}
		public boolean ready() throws IOException
		{
			return br.ready();
		}
		public long nextLong() throws IOException
		{
			return Long.parseLong(next());
		}
	}
}