Light glows for every 20 seconds

Light glows for every 20 seconds . How many max. times did it glow between 1:57:58 and 3:20:47 am.

This problem repeats another one in the library (at most with different numbers), so it's left out of browsing.

~8 minAnswer checked instantly

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #9069

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