Why do computers store all information as binary numbers? (B) This requires no translation of data after it is entered by the user.

Transcription

1 Week2 Quizzes (Aug30- Sept1) L4 Quiz 1 Why do computers store all information as binary numbers? (A) This is easier to use than base 10 numbers. (B) This requires no translation of data after it is entered by the user. (C) This only requires 2 memory states. (D) This helps memories be small.

2 L4 Quiz 2 The Central Processing Unit (CPU) does all the following except... (A) Fetches instructions and data from memory (B) Stores large quantities of data (C) Performs computations on the data based on the instructions (D) Sends results to output devices

3 L5 Sept 8 th Why def is not a valid Python name? A) the name is too short B) the name contains only lower case characters C) def is a Python reserved word

4 L6 Sept. 8 th A color is gray when: A) the red component is the same as the green one B) the red component is the same as the blue one C) the blue component is the same as the green one D) all the components have the same value

5 L7 Sept. 15 th Which of the following assertion about pictures is false? A) A picture has two dimensions: Width and Height B) A picture is the main memory representation of an image file C) A picture is a matrix of pixels D) A picture is a matrix of colors

6 L8 Sept. 20 th Consider the following function: def decreasered(pict): allpixels = getpixels(pict) for p in allpixels: value = getred(p) setred(p, value*0.5) Which of the following statements about it is false: A) you must load the function in the JES command area before executing it B) pict is an input parameter C) you cannot print the variable value in the JES command area after you execute the function D) the function decreasered decreases the red component of each pixel of the picture pict E) the function decreasered decreases the red component of the last pixel (i.e. bottommost, rightmost) of the picture pict

7 L10 Sept. 27 th print range(10,1,-5) will print : A) the empty sequence [] B) [10, 5, 1] C) [10, 5] D) will result in an error because the last parameter can not be negative

8 Oct 6th quiz Assume you have a picture with width 200 and height 60. We want to rotate the picture left by 180 degrees and then scale up the picture of a factor 5.Which dimensions should the have the empty picture we will use? A Newpict = makeemptypicture (200, 60) B Newpict = makeemptypicture (1000, 300) C Newpict = makeemptypicture (60, 200) D Newpict = makeemptypicture (300, 1000)

9 Oct 6th quiz The volume of a sound: A) depends on the frequency of the wave B) depends on the wavelength C) depends on the sampling rate D) depends on the amplitude of the wave

10 Oct 18th quiz The frequency of a sound wave: A) depends on the sampling rate B) depends on the amplitude of the wave C) is measured in DB D) is measured in number of cycles per second

11 Oct 25th What does the following function does? def myfunc(source): len = getlength(source) / target = makeemptysound(len) targetindex = 0 for sourceindex in range(0, getlength( source), 2): value = getsamplevalueat( source, sourceindex) setsamplevalueat( target, targetindex, value) targetindex = targetindex + 1 play(target) return target A) doubles the volume of a sound B) halves the volume of a sound C) doubles the frequency of a sound D) halves the frequency of a sound

12 Oct 27th quiz Consider the following function: def myfunc(): cont1=0 for x in range(0, 10): count1 = count1 + i return The function above: A) will cause an error when it is loaded B) will return 0 C) will return 45 D) will return None

13 Nov 1st quiz Consider the following function: def myfunc(): cont1=0 for x in range(0, 10): count1 = count1 + x If you want to assign to a variable (result) the output produced by the function above (i.e. result = myfunc()) : A) you do not need to change anything in the function B) you must add a return statement: return C) you must add a return statement: return count1 D) you must add an input parameter count1

14 Nov 8th quiz Suppose we have a string test: >>> test="this is a test." Which of the following statements will NOT result in an error? i) print test.startswith(this) ii) print startswith(test) iii) print test.startswith( this ) iv) print test.startswith( this ) A) only iii) B) iii) and iv) C) ii) D) none of them

15 Nov 10th quiz Which of the following command results in a JES error? A) print "Mark" + "Mark" B) print "Mark" + 2 C) print "MarkMark" D) print "Mark" * 2

16 Nov 15th quiz Given the following URL: Which of the following statements is WRONG? 1) http is the protocol used 2) web.ics.purdue.edu is the path to the resource 3) web.ics.purdue.edu is the domain name 4) /~cs180/fall2010cs177/recitation_slides/rec1.ppt is the path to the resource A) 1 B) 2 C) 3 D) 4

17 Nov 22nd quiz What is an HTTP server? A) a software that transforms domain names into IP addresses B) another name used to indicate a Web server C) a software that displays HTML pages D) none of the above

18 Nov 29th quiz Consider the two algorithms of slide 36 of Chapter14 Which of the following statements is the correct one? A) they have the same complexity because they both implement a sampling algorithm B) they have the same complexity: O(n**2) C) they have the same complexity: O(n) D) copybarbsfacelarger() has complexity O(n**2) and half(filename) has complexity O(n).

19 Dec 1st quiz If you want to grab a web page content from a Python program, which Python module you should import? A) none B) the os module C) the random module D) the urrlib module

20 Dec 6st quiz Suppose we have a string test: >>> test = "this" Which of the following statements will NOT result in an error? i) print isalpha(this) ii) print isalpha(test) iii) print test.isalpha( this ) iv) print test.isalpha() A) only iv) B) iii) and iv) C) ii) D) none of them