In a recent article it was reported that 35.4% of all high school students smoke cigarettes. 65% of these students plan on going to college. What is the probability that a randomly selected student smokes cigarettes and plans on going to college?

If the sender and receiver each use a different key the system is referred to as __________ encryption.

A. secret-key ? B. conventional ? C. single-key ? D. asymmetric

The _________ algorithm performs various substitutions and transformations on the plaintext.

A. keystream ? B. cipher ? C. encryption ? D. codebook