Imagine the bottom stave in each pair is played with r.h. Those are the notes to play. BUT - they're all played with l.h. as it's the bottom stave. Reason is simple. Those notes could be written in bass clef(F clef), but they'd all be on leger lines, and be a little more tricky to read.
It could all have been written in the 'normal' way,but an octave lower, with '8va' included,to sound the same, and be as easy/difficult to play.
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