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#include <cstdio>
#include <vector>
#include <unordered_map>
#include <set>
#include <algorithm>

using namespace std;
typedef pair <int, int> P;
const int MAXN = 3000;
const int MAXK = 4;
const int MOD = 1000000007;

int n, k;
int result;
char word[MAXN + 5];
bool t[MAXN + 5][MAXN + 5];

set <vector <int> > M;
unordered_map<int,bool>::iterator it;

inline int encode(int x, int y);
inline P decode(int e);
inline vector <int> get_neighbours(int e);

void solve(int used, unordered_map<int, bool> taken, vector <int> possible);

int main() {
  scanf("%d %d", &n, &k);
  for(int i = 0; i < n; ++i) {
    scanf("%s", word);
    for(int j = 0; j < n; ++j) {
      if(word[j] == '#') t[i + 1][j + 1] = true;
    }
  }
  unordered_map<int, bool> taken;
  vector <int> possible;
  for(int i = 1; i <= n; ++i) {
    for(int j = 1; j <= n; ++j) {
      if(t[i][j]) {
        taken[encode(i - 1, j - 1)] = true;
      } else {
        if(t[i - 1][j] or t[i][j - 1] or t[i + 1][j] or t[i][j + 1]) {
          possible.push_back(encode(i - 1, j - 1));
        }
      }
    }
  }

  if(k == 1) {
    printf("%d\n", possible.size() % MOD);
  } else {
    solve(0, taken, possible);
    printf("%d\n", result % MOD);
  }
  return 0;
}

inline int encode(int x, int y) {
  return n * x + y;  
}

inline P decode(int e) {
  int x, y;
  y = e % n;
  x = (e - y) / n;
  return make_pair(x, y);
}

inline vector <int> get_neighbours(int e) {
  int x, y;
  P tmp = decode(e);
  x = tmp.first, y = tmp.second;
  vector <int> neighbours;
  if(x - 1 >= 0) neighbours.push_back(encode(x - 1, y));
  if(y - 1 >= 0) neighbours.push_back(encode(x, y - 1));
  if(x + 1 < n) neighbours.push_back(encode(x + 1, y));
  if(y + 1 < n) neighbours.push_back(encode(x, y + 1));
  return neighbours;
}

void solve(int used, unordered_map<int, bool> taken, vector <int> possible) {
  if(used == k) {
    vector <int> tmp;
    for(it = taken.begin(); it != taken.end(); ++it) {
      tmp.push_back((*it).first);
    }
    sort(tmp.begin(), tmp.end());
    if(M.find(tmp) != M.end()) return;
    M.insert(tmp);

    result++;
    if(result > MOD) result %= MOD;
    return;
  }

  vector <int> tmp_p = possible;
  unordered_map<int, bool> tmp_t = taken;
  for(int i = 0; i < possible.size(); ++i) {
    int ps = possible[i];
    vector <int> tmp_p = possible;
    unordered_map<int, bool> tmp_t = taken;
    swap(tmp_p[i], tmp_p[tmp_p.size()-1]);
    tmp_p.pop_back();

    tmp_t[ps] = true;
    vector <int> neighbours = get_neighbours(ps);
    for(int i = 0; i < neighbours.size(); ++i) {
      int neighbour = neighbours[i];
      if(tmp_t.find(neighbour) == tmp_t.end()) {
        tmp_p.push_back(neighbour);
      }
    }
    sort(tmp_p.begin(), tmp_p.end());
    tmp_p.erase(unique(tmp_p.begin(), tmp_p.end()), tmp_p.end());

    solve(used + 1, tmp_t, tmp_p);
  }
}