Confused question!
If the author intended the primary key is clustered, this apply (from BOL):

When a constraint that created a clustered index is deleted, the data rows that...

Here a cursor free version:
DECLARE @TableName SYSNAME = 'MyTable',@Schema SYSNAME = 'dbo', @sql NVARCHAR(MAX) = '', @max-2 INT
,@UnionALL NVARCHAR(11)= '';

SELECT @sql += @UnionALL +...

Assuming we use DBCC SQLPERF with the parameter LOGSPACE the explanation is wrong.
"Check the amount of space available in a transaction log file."

BOL says the opposite "amount...

About the "tempdb", here says that it is configured at the smallest possible size.
https://docs.microsoft.com/en-us/sql/database-engine/configure-windows/start-sql-server-with-minimal-configuration

Correct and incomplete answer: "This lets me know if the Order table is in the buffer pool", it always returns false.
Ambiguous answer: "This tells me nothing as tables cannot...

The best method is the following:
SELECT COUNT(*) FROM sys.triggers
WHERE parent_id = OBJECT_ID('TriggerTest')