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#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <queue>
#include <stack>
#include <cstdio>
#include <set>
#include <map>
#include <string>
#include <queue>
#include <stack>
#include <unordered_set>
using namespace std;

typedef long long int LL;
typedef long double LD;
typedef vector<int> VI;
typedef vector<LL> VLL;
typedef vector<LD> VLD;
typedef vector<string> VS;
typedef vector<VS> VVS;
typedef pair<int, int> PII;
typedef vector<PII> VPII;

const int INF = 1000000001;
const LD EPS = 10e-9;

#define FOR(x, b, e) for(int x = b; x <= (e); ++x)
#define FORD(x, b, e) for(int x = b; x >= (e); --x)
#define REP(x, n) for(int x = 0; x < (n); ++x)
#define VAR(v, n) __typeof(n) v = (n)
#define ALL(c) (c).begin(), (c).end()
#define SIZE(x) ((int)(x).size())
#define FORE(i, c) for(VAR(i, (c).begin()); i != (c).end(); ++i)
#define MP make_pair
#define PB push_back
#define ST first
#define ND second
#define abs(a) ((a)<0 ? -(a) : (a))
#define max(a, b) ((a) > (b) ? (a) : (b))
#define min(a, b) ((a) < (b) ? (a) : (b))

const int MAX_N = 3005;
const int DIRS = 4;

bool operator<(const VS& a, const VS& b)
{
    for(int i = 0; i < a.size(); ++i)
    {
        if(a[i] == b[i])
            continue;

        return a[i] < b[i];
    }

    return false;
}

int n, k;
VS grid;
VPII tilesPos, newTiles;
set<VPII> all;
int xMoves[] = {-1, 0, 1, 0};
int yMoves[] = {0, 1, 0, -1};

void simulate(int stage)
{
    if(stage == k)
    {
        VPII newTilesCopy = newTiles;
        sort(newTilesCopy.begin(), newTilesCopy.end());
        all.insert(newTilesCopy);

        return;
    }

    for(int i = 0; i < tilesPos.size(); ++i)
    {
        for(int j = 0; j < DIRS; ++j)
        {
            int x = tilesPos[i].second+xMoves[j];
            int y = tilesPos[i].first+yMoves[j];

            if(x >= 0 && x < n && y >= 0 && y < n && grid[y][x] == '.')
            {
                grid[y][x] = '#';
                tilesPos.push_back(MP(y,x));
                newTiles.push_back(MP(y,x));

                simulate(stage+1);

                newTiles.pop_back();
                tilesPos.pop_back();
                grid[y][x] = '.';
            }
        }
    }
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin >> n >> k;
    grid = VS(n);

    REP(i, n)
    {
        cin >> grid[i];

        for(int j = 0; j < n; ++j)
        {
            if(grid[i][j] == '#')
            {
                tilesPos.push_back(MP(i,j));
            }
        }
    }

    simulate(0);

    cout << all.size()%1000000007 << endl;

    return 0;
}