Vigenère Cipher Practice Problems Online

A certain message is encoded with a 2 letter key. The encrypted message is

1	`BWGWBHQSJBBKNF`

We also happen to know that the second character of the plain-text is "I". Break the cipher and find the answer.

The following message is encrypted(via the Vingenre cipher) with the key DAMNDANIEL

1	`WHQNQSJMVERTTVVPEWFWHMUFIIIMLFQDDRGFBZXJIOGEWRVTPTRNRVYEUCROUEPSLFGGWTABUYOIBVWTAHGAGRRLWPYEZGBSRDIYPIXYLOAMMRKTTHQDEMHPLGTGBNVVIEKOGFDNQVMYHHGAGRRL`

Decipher the message to obtain the answer.

The string

1	`PETERPIPERPICKEDAPECKOFPICKLEDPEPPERS`

is encrypted with a key of unknown length. The resulting cipher text is

1	`RGVGTRKRGTRKEMGFCRGEMQHRKEMNGFRGRRGTU`

What is the length of the key?

Vigenère Cipher