Homework Helper Expl. 4

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	Exploration 4 Homework Helper. How Have Satellites Changed Since Sputnik? Communications satellites (link 1 \| link 2) Weather satellites (link 1 \| link 2 \| link 3) Navigation satellites (link 1 \| link 2 \| link 3) Reconnaisance satellites (link 1 \| link 2) Environmental satellites (link 1 \| link 2) How do satellites stay in orbit (link 1 \| link 2 \| link 3) Anti-satellite weapons (link 1 \| link 2 \| link 3)