#include <stdio.h>
#include <stdlib.h>

int compar(const void *a, const void *b) {
        return *(int *)a - *(int*)b;
}

int readline( int m ) {

    char str[1024];
    char ch;
    int count = 0 , i = 0;

    scanf("%s" , str);

    for ( i = 0 ; i < m ; i++ ) {
//      printf("ch = %c\n" , ch);
        if ( str[i] == '*' )
            count ++;
    }

    return count;
}

int main ( int argc , char * argv[] ) {

    int t;
    scanf("%d" , &t);
    getchar();

    while ( t-- ) {
        int n , m , i , k;
        scanf("%d%d%d" , &n,&m,&k);
        int * array = (int *) malloc ( n * sizeof(int) );

        //printf("n = %d and m = %d and k = %d\n" , n , m , k);
        for ( i = 0 ; i < n ; i++ ) {
            //printf("Reading line : \n");
            array[i] = readline(m);
        }

        //printf("Before:\n");
        //for ( i = 0 ; i < n ; i++ ) {
        //  printf("%d " , array[i]);
        //}
        //printf("\n");
        for ( i = 0 ; i < k ; i++ ) {
            qsort(array , n , sizeof(int) , compar);
            array[0] = m - array[0];
        }

        //printf("After:\n");
        //for ( i = 0 ; i < n ; i++ ) {
        //  printf("%d " , array[i]);
        //}
        //printf("\n");

        for ( i = 1 ; i < n ; i++ ) {
            array[0] += array[i];
        }

        printf("%d\n" , array[0]);

    }

    return 0;
}