According to the maintenance manual for the Svartsengi Island geothermal plant in Iceland, every six months the operators must change the gearbox oil and regrease all electric motors and couplings. Without humans to perform these sorts of maintenance procedures, some plants might run for a few years, but they’d all succumb to corrosion eventually.

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the dominoes began to fall. the surrender at appomattox took place a week later on april 9. while it was the most significant surrender to take place during the civil war, gen. robert e. lee, the confederacy's most respected commander, surrendered only his army of northern virginia to union gen. ulysses s. grant

explanation:

this is a good question! i'll do some research and come back when i have the answer!

cultural history is your answer