1) We used the hash of an obviously made up public key. This means the difficulty would be in even finding a public key with such a hash, much less finding the corresponding private key

2) To create the valid non-redeemable address for destroying coins, we will use this online address generator: http://gobittest.appspot.com/Address

Using this byte sequence as public key to return invalid: (Section 1 - Public ECDSA Key)

0800000000000000000000000000000000000000000000000000000000000000000000000000000 000000000000000000000000000000000000000000000000000

Enter this line to "Public ECDSA Key" field and press "Send" button - This will return the error "Invalid public key length". After this you need to set the correct address version. Go down to section 4 and edit the first byte of "Adding network bytes to 3" field, set it to 4D Yang and 8C for Yin(First two characters). Now you can press "Send" button and get the Yin or Yang address used for destroying the coins, which corresponds to invalid public key.