Be sure to show all work. No credit will be given without showing each step in the process.

Problem #$3$: Columnar transposition.

Use columnar transposition, as discussed in class, to encrypt and decrypt the following message attack postponed until two am using a key of sonic

Asymmetric encryption

Use the RSA algorithm

Review this "RSA Algorithm" video. Also, you can review the RSA wikipedia page example.

Students can use a calculator such as WolframAlpha to help with this modular arithmetic. But you should understand the principles well enough to perform the calculations by hand with these problems.

Problem $4$: Use the RSA algorithm to encrypt and then decrypt the number $9$ to ciphertext using $p=5,q=11,e=3.$ Again, show all work $($for example, how was d calculated$).$