The variables xdomain, xrange, ydomain, yrange, cdomain and crange have been initialized with the same array [0,1]. Modify these arrays so that the d3.scaleLinear objects xs, ys and cs correctly map data values and indices to the desired display values. The scale xs() should map data values so the bars extend from zero to as much as 100 pixels. The scale ys() should map the top edge of the bars from 100 to 250.The scale xs() should set the colors of the bars based on the data value, extending from "blue" for a data value of zero, to "orange" for the maximum data value.

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.