Reduced, irreducible and integral schemes

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I am studying properties of schemes and I have the following problem.

Let $R$ be a ring, $S=Spec(R)$, $n\in\mathbb{N}$ an integer. Show that the following are equivalent:

  1. $S$ is reduced (resp irreducible, resp integral)
  2. $\mathbb{A}^n_R$ is reduced (resp irreducible, resp integral)
  3. $\mathbb{P}^n_R$ is reduced (resp irreducible, resp integral)

I know that a scheme $S=Spec(R)$ is reduced if and only if nil$(R)=0$; it is irreducible if and only if nil$(R)$ is prime; and it is integral if and only if it is both reduced and irreducible.

If someone can help me, it would be very appreciated.