1+NULL SQL Intreview question

 ---Product base interview question
--Mention the output.
-- #15day SQL CHALLENGE

--DAY-3
---Please  Findout the below question & answer--------------------------------------------------

SELECT 1+NULL --NULL
SELECT '1'+NULL --NULL
SELECT '1'+'NULL' --1NULL
SELECT 1+'NULL' --Conversion failed when converting the varchar value 'NULL' to data type int.

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