formal deduction

[true pawn]

Hello! I am studying formal deduction for my upcoming logic exam but I am not sure how (in the example given below) my teacher started the proof (how did he use A1).
I tried writing my version of how I'd do it on the left ( I started from the bottom and worked my way up).

[stone snow]

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[analog lake]

M.P most probably means modus pones or sth

Modus ponens

Uses 1,2 to get the implication in 3?

[true pawn]

nvm i understand now

thanks

+close

[rocky oracle]

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[rocky oracle]

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