Skyrim elder scrolls V: what level of destruction can you get spell tome fireball?

In skyrim I wanted to know where to get or buy the spell "fireball". If you can buy it where and what level do u have to be. And if you can get it in a dungeon, pls tell me where. THANKS ;)Skyrim elder scrolls V: what level of destruction can you get spell tome fireball?
It's an adept level spell, so just shy of 50 Destruction. The Court Wizard in Whiterun, possibly also as random loot.Skyrim elder scrolls V: what level of destruction can you get spell tome fireball?
its an ADEPT level spellSkyrim elder scrolls V: what level of destruction can you get spell tome fireball?
The Mage at dragonsreach castle in Whiterun has it. I was just below 50 destruction when i realized he had it available.
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