if(ds.Tables[0].Rows.Count>=7){
string[] columnsToCheck = new string[]{"authoritites_Name","authoritites_Designation","authoritites_Contact"};
bool isAllColumnsNull = columnsToCheck.All(k=> string.IsNullOrEmpty( ds.Tables[0].Rows[6][k]+""));
if(!isAllColumnsNull){
}
}