A requirement for a cipher is that every plaintext letter corresponds to a different ciphertext letter. If a and b are not relatively prime to n, does the affine cipher meet this property? If so, prove it. Otherwise, present a counterexample. Show your work.

Write a program that prompts the user to input a string. the program then uses the function substr to remove all the vowels from the string. for example, if str = "there", then after removing all the vowels, str = "thr". after removing all the vowels, output the string. your program must contain a function to remove all the vowels and a function to determine whether a character is a vowel.

While inserting images, the picture command is usually used to insert photos from a digital camera, and the clip art command is usually used to a.edit the sizes and other characteristics of photos that have been inserted. b.take a screenshot of an image and copy it to the clipboard for pasting. c.search for drawings or other images from a library of prepared pictures. d.make illustrations using lines and shapes that are easy to manipulate.

What is a loop? a. a collection of function definitions at the top of a program b. a line of code that defines a variable and assigns it a value c. a program that opens the turtle graphics window d. a block of code that repeats a specific number of times