How to model a Dodecahedron from scratch

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Create a pentagon sketch, form a surface body, save as part, use "Create Assembly From Part," insert and fix the pentagon in assembly, control-drag copy into assembly and orient. Mate two edges, then another copy with mates to define model. Repeat for three more pents, forming subassembly and control-dragging into main assembly. Match orientation and mate corner points. Save assembly as part file, open it, knit surfaces and select "Try to form solid," applying fillet to external surfaces. A dodecahedron is born with ease!