List down all of the sales IDs for sales handled by sales people with first name starting with alphabet "s".
first name starting with alphabet "s" refers to FirstName LIKE 's%';
SELECT T1.SalesID FROM Sales AS T1 INNER JOIN Employees AS T2 ON T1.SalesPersonID = T2.EmployeeID WHERE SUBSTR(T2.FirstName, 1, 1) = 's'