Which of the following is true? a. There are RFCs that describe challenge-response authentication techniques to use with email. b. Filtering for spam sometimes produces a false positive, in which legitimate email is identified as spam. c. Spam relies heavily on the absence of email authentication. d. All of the above.

Give an example of a case where a two-way handshake to establish a connection could leave one side of the connection live while the other side does not believe there is a connection.

You have written, as part of a school assignment, a research paper on the solar system. you want to share this paper on your school website. on which type of server will you upload it?

1. ask the user how many questions are in the quiz. 2. ask the user to enter the key (that is, the correct answers). there should be one answer for each question in the quiz, and each answer should be an integer. e.g., 34 7 13 100 81 3 9 10 321 12 might be the key for a 10-question quiz. you will need to store the key in an array. 3. ask the user to enter the answers for the quiz to be graded. there needs to be one answer for each question. note that these answers do not need to be stored; each answer can simply be compared to the key as it is entered. 4. when the user has entered all of the answers to be graded, print the number correct and the percent correct. 5. add a loop so that the user can grade any number of quizzes with a single key. after the results have been printed for each quiz, ask "grade another quiz? (y/n)." note: you only have one array (the key). you are not creating a new key for each set of quiz answers.