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Holditinplaceormoveitalong.Screwsdobothjobsallday long.
ByGlen Phelan
Simple
Machines
Explorer magazine’s six‑part series
SimpleMachines
Explorermagazine’ssix‑part series
This edition
HumanJourney
PhysicalScience
Beforeyoudothescienceactivityattheendofthisarticle,thinkabouthowyouwillrecordthe results.