Force checkmate by sacrificing

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MaestroDelAjedrez2025
How can you force checkmate in these positions by sacrificing material?

Octaviano2012

en la ultima dama h6, alfil g3 y luego dama a g3

Octaviano2012

no pude resolver las otras no tengo tiempo ahora

Idrinkyourhealth3

i solved all thanks. What is the level of these puzzles ? like 1000-1100 ?