(10 points - Key dependent message security). Several works design cryptographic schemes such as specifies a function f and receives encryption ER(f(k)), i.e., encryption of the message f(k) where k is (a). Extend the definition of secure pseudo-random function for security against key-dependent message attacks b). Suppobe that F is secure pseudo-random function. Show a ('weird') function F which is also a secure pseudo-random function, but not secure against key-dependent message attacks