Where to find sql server query cost

Hi Expert,

I run the query from exam 433 book, it said this query cost is 151, where I can find this number? Thanks in advance.


USE AdventureWorks;

SELECT
    soh.SalesOrderID
    ,soh.OrderDate
    ,(
        SELECT TOP(1)
            sod1.UnitPrice
        FROM Sales.SalesOrderDetail AS sod1
        WHERE sod1.SalesOrderID = soh.SalesOrderID
        ORDER BY sod1.OrderQty DESC
    ) AS UnitPrice
    ,(
        SELECT TOP(1)
            sod2.OrderQty
        FROM Sales.SalesOrderDetail AS sod2
        WHERE sod2.SalesOrderID = soh.SalesOrderID
        ORDER BY sod2.OrderQty DESC
    ) AS OrderQty
FROM Sales.SalesOrderHeader AS soh
WHERE soh.TerritoryID = 4;