Part $1$:$($Encryption and Decryption$)(3$ pts$)$

The function $E(x)=(ax+b)$ MOD $26$ defines a valid Affine cipher of a letter $\text{'}x\text{'}.$ the coefficients $\text{'}a\text{'}$ and $\text{'}b\text{'}$ are

integers between $0$ and $25,$ and $\text{'}a\text{'}$ has to be relatively prime to $26.$

Recall that the numerical equivalents of the English letters are as follows:

Encrypt the plaintext "NETWORK SECURITY" with the Affine cipher $E(x)=(11x+5)mod26.(1pt)$

$E^{-1}(y)=(cy+d)MOD26E(x)E^{-1}(y)$