Answer:
- function processNumbers(numList){
- try{
- for(let i=0; i < numList.length; i++){
- if(isNaN(numList[i])){
- throw "All elements in the list should be numbers.";
- }
-
- }
- }
- catch(err){
- console.log(err);
- }
- }
-
- let myList = [4, 6, 1, "abc", 9];
- processNumbers(myList);
Explanation:
The solution code is written in JavaScript as the isNaN() is an in-built function in JavaScript.
Firstly, create a function processNumbers that takes one input number list, numList (Line 1).
To handle the possible Not a Number (NaN) error, create a try and catch block. In the try block, create a for-loop to traverse through the numList array and use isNaN function to check if the current value is a number (Line 3 - 4). If it is not a number, isNaN will return true and the program will run the throw statement (Line 5). The throw message will be passed to the catch block and display it on console (Line 10 - 12).
We can test the function by using the sample list (Line 15 - 16) and we shall see the thrown error message is displayed.
Its false nothing comes up when u press that key
Answer B: Asymmetric cryptography, because the receiver has its own decryption key and cannot create encrypted messages, because he doesn't have the encryption key.
About the other answers:
A: Private keys are always involved, there has to be some secret to do encryption, so this answer doesn't say very much.
C: Digital signatures can be used to verify/prove some data comes from some person (the signer) in an unaltered way. It is not about encryption, so is not about the security of your message. You use it in combination with encryption.
D: Like A, this doesn't say very much. Shared secret keys (symmetric keys) can be used for encryption, but they are less secure since the keys have to exist in more than one place (sender and receiver).
Answer:
The only element visible is the presentation itself.
Explanation:
All of the other options, such as presenter's assistance, is hidden away from the projector, presentation device, etc. You are the only one that can see the window that shows what slide is next, presenter's notes, etc. <u>In other words, whatever you want the audience to see, that is only what they will see and nothing else.</u>