public string GetAdminEmails()
        {
            TAC_Team4Entities db   = new TAC_Team4Entities();
            List <string>     list = db.TAC_User.Where(x => x.IsAdmin == true).Select(x => x.Email).ToList();
            StringBuilder     sb   = new StringBuilder();

            foreach (string item in list)
            {
                sb.Append(item);
                sb.Append(" ");
            }
            return(sb.ToString());
        }