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Suppose that $T$ is a linear transformation from $R^n$ into $R^m$.

Assume $n\neq m$.

Which of the following statements is TRUE?

$T$ can be represented by an $n\times m$ matrix.

$T$ can be represented by an $m\times n$ matrix.

$T$ can be represented by an $n\times n$ matrix.

$T$ can be represented by an $m\times m$ matrix.

There is not enough information given to determine the dimensions of the matrix that would represent $T$ or even if such a matrix exists.