plzz answerr!!!!
will mark as brainlist!!
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Answer:
16160
Step-by-step explanation:
(2021#2020)= [tex]2021^2-2020^2=4041[/tex]
(2020#2019)=[tex]2020^2-2019^2=4039[/tex]
finally, (2021#2020)#(2020#2019)= [tex]4041^2-4039^2=16160[/tex]