#include <bits/stdc++.h>
using namespace std;
int n;
char s[150];
int main() {
  int len, i, j, t = 0;
  scanf("%d", &n);
  for (i = 0; i < n; i++) {
    t = 0;
    scanf("%d %s", &len, s);
    for (j = 0; j < len / 2; j++) {
      if ((s[j] - s[len - j - 1]) == 2 || (s[len - j - 1] - s[j]) == 2 ||
          s[j] == s[len - j - 1]) {
        continue;
      }
      t = 1;
      break;
    }
    if (t == 1)
      printf("NO\n");
    else
      printf("YES\n");
    for (j = 0; j <= len; j++) {
      s[j] = 0;
    }
  }
  return 0;
}
