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**pece** This is correct : $\displaystyle 5\times 29 = 145 = 4\times 36 + 1$

The table gives you a correspondence $\displaystyle C : \{A,\dots,Z\} \rightarrow \{1,\dots,26\}$. So for a letter $\displaystyle \alpha$, the cipher letter is $\displaystyle C^{-1}(E(C(\alpha)))$ (I didn't check, but in order to apply $\displaystyle C^{-1}$, one must have $\displaystyle m^5 (\mathrm{mod}\, 37) \in \{1,\dots,26\},\ \forall m\in\{1,\dots,26\}$).

When you have a word, it's a sequence of letter : you encrypt every letter of this sequence and have this way a sequence of cipher letter. It's your cipher text.