Finding the characteristic polynomial of a matrix given these kernels

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I'm given that $A$ is an $8 \times 8$ matrix, and then I'm given the dimensions of the kernels for $A - 2I$ raised to powers $1$ and $2$, as well as dimensions for the kernels of $A - 3I$ raised to powers $1$, $2$ and $3$.
In general terms, how do I use this information to learn about the characteristic polynomial of $A$?
I assume the Rank-Nullity theorem comes into play.

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If some $(A - \lambda I)^m$ has kernel of dimension $d$, then the characteristic polynomial of $A$ is divisible by $(z-\lambda)^d$.