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#include <bits/stdc++.h>
#define rep(a, b) for(int a = 0; a < b; a++)
#define pb push_back
#define var(a, b) __typeof(b) a = b
#define foreach(a, b) for(var(a, (b).begin()); a != (b).end(); a++)

using namespace std;
typedef long long ull;

const int MAX = 3002;
const int MOD = 1e9+7;
bool c[MAX][MAX];

const int X[] = {0, 1, 0 , -1};
const int Y[] = {1, 0, -1, 0};

ull Oblicz(bool c[MAX][MAX], int n, int k, int x, int y){
    ull wyn = 0;
    for(int i = y; i <  n; i++) for(int j = x; j < n; j++){
        rep(r, 4)
            if(c[i][j] == false &&
               i + X[r] < n && i + X[r] >= 0 &&
               j + Y[r] < n && j + Y[r] >= 0 && c[i+X[r]][j+Y[r]] == true){
                    c[i][j] = true;
                    if(k == 1) wyn = (wyn + 1)%MOD;
                    else wyn = (wyn + Oblicz(c, n, k-1, i, j))%MOD;
                    c[i][j] = false;
                    break;
               }
    }
    return wyn;
}

int main(){
    ios_base::sync_with_stdio(0);
    int n, k;


    cin >> n >> k;

    char ch;
    rep(i, n) rep(j, n){
        cin >> ch;
        if(ch == '#') c[i][j] = true;
        else c[i][j] = false;
    }

   cout << Oblicz(c, n, k, 0, 0);
}