Q10- i-How many keys are necessary for messaging between Bob and Alice if they use symmetrickey cryptography? ii- When is the symmetric key cryptographi unsafe? Why? Q11- Which of the following items shall be hidden for safety according to Kerckhoff principle? ( ) Plaintext Messages, ( ) Ciphering Algorithms ( ) Deciphering Algor. ( ) Ciphered Messages ( ) Public Keys ( ) Private Keys Q12- i- What is a node of NodeRED, ii- What does a node process? iii- Which node can get an ASCII text from UART? iv- Which node can transfer text to NodeRED when clicked on dashboard v- Which node can transfer commands through UART to a low-end processor. Q13- How can you connect a serial output of Arduino simulation to the NodeRed Serial Node? Q14- For the given NodeRED diagram i- If you click on the left button of "c320 hello" node, where does the message appear? ii- If Arduino transmits "0", "1", .., "9" periodically at every 2 seconds, what will appear on the dashboard