Determine if the following extensions are normal

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I wish to determine if the extension

1) $L = Q(e^{2πi/n})$ is normal over $Q$,

2) $K(a)$ is normal over $F_3(t)$ where $a$ is root in a splitting field of $x^3-t$

For 1) Is it like polynomial $x^n-1$ splits completely in $Q(e^{2πi/n})$?

For 2) Is the idea like $K(a)$ is an extension of degree 3 over $Q$ but if it is normal then it contains all roots of the polynomial which leads to a contradiction of the degree?