Answer:-

Note:
Implicit transaction mode remains in effect until the connection executes a SET IMPLICIT_TRANSACTIONS OFF statement, which returns the connection to autocommit mode. In autocommit mode, allindividual statements are committed if they complete successfully.
When a connection is in implicit transaction mode and the connection is not currently in a transaction, executing any of the following statements starts a transaction:
ALTER TABLE (DDL)

FETCH -

REVOKE -

BEGIN TRANSACTION -

GRANT -

SELECT -

CREATE (DDL)

INSERT -

TRUNCATE TABLE -

DELETE (DML)

OPEN -

UPDATE (DML)

DROP (DDL)

Note 2: XACT_STATE returns the following values.
1 The current request has an active user transaction. The request can perform any actions, including writing data and committing the transaction. The transaction is committable.
-1 The current request has an active user transaction, but an error has occurred that has caused the transaction to be classified as an uncommittable transaction.the transaction is uncommittable and should be rolled back.
0 There is no active user transaction for the current request. Acommit or rollback operation would generate an error.

Reference:-https://technet.microsoft.com/en-us/library/ms187807(v=sql.105).aspx
https://technet.microsoft.com/en-us/library/ms189797(v=sql.110).aspx

Answer:-

Delete up to 4000 rows at a time. Keep doing it until all rows have been deleted.

Note that @@ROWCOUNT returns the number of rows affected by the last statement.

Reference:-https://msdn.microsoft.com/en-us/library/ms187316.aspx

Answer:-
When deadlocks occur, trace flag 1204 and trace flag 1222 return information that is capturedin the SQL Server error log. Trace flag 1204 reports deadlock information formatted by each node involved in the deadlock. Trace flag 1222 formats deadlock information, first by processes and then by resources.

The output format for Trace Flag 1222 only returns information in an XML-like format.

Reference:-https://technet.microsoft.com/en-us/library/ms178104(v=sql.105).aspx

Answer:-1. Yes

Reference:-https://docs.microsoft.com/en-us/sql/relational-databases/databases/tempdb-database?view=sql-server-2017

Answer:-
1. LockAcquired

The Lock:Acquiredevent class indicates that acquisition of a lock on a resource, such asa data page, has been achieved.

The Lock:Acquired and Lock:Released event classes can be used to monitor when objects are being locked, the type of locks taken, and for how long the locks were retained. Locks retained for long periods of time may cause contention issues and should be investigated.