1039
xkcd #3135: Sea Level
(imgs.xkcd.com)
Title text:
They're up there with coral islands, lightning, and caterpillars turning into butterflies.
Transcript:
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Source: https://xkcd.com/3135/
No, no, no; We're just giving Mercury a retro-grade.
I'm thinking maybe a C to C+ at best. I mean it's kinda 'retro', but that's definitely not the first description that comes to mind.