It's been a very long time since people have been able to witness a solar eclipse across the entire country.

On Monday August 21st, more than seven million people across the US are expected to witness the first total solar eclipse since 1918.

Companies across the country are already tallying up the cost to productivity that the eclipse will cause because as with all exciting things, it will happen smack in the middle of the workday. In Chicago alone, the cost to employers is predicted to hit $28 million.

Since there's a very good chance that you won't see another total eclipse in your lifetime, we compiled everything you need to know to make the most of the big day.

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