JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 359 · 40 questions

Code tip (Line by line): let x = 5; makes a variable x holding 5; x = x + 2; changes it to 7. console.log(…) writes in the console; alert(…) shows a pop-up box. Text in quotes + anything = joined text: "5" + 3 → "53".

1. 1.⚡ Where does console.log() show its output? (a) on the printer (b) on the title bar (c) in the address bar (d) in the console
2. 2.⚡ What number does this code print?
   let a = 51;
   let b = 33;
   console.log(a + b);
3. 3.⚡ Which word makes a new variable? (a) put (b) let (c) give (d) make
4. 4.⚡ What does JavaScript add to a web page? (a) only colours (b) the domain name (c) actions and changes (d) the page title
5. 5.⚡ What does this code show?
   let name = "Meera";
   alert("Welcome, " + name + "!"); (a) Meera (b) Welcome, Meera! (c) name (d) Welcome, name!
6. 6.⚡ What does this code show?
   let name = "Zoya";
   console.log("Hello, " + name + "!"); (a) Hello, name! (b) Hello, Zoya! (c) Zoya (d) name
7. 7.⚡ Which JavaScript word makes a new variable? (a) if (b) for (c) alert() (d) let
8. 8.⚡ Which JavaScript word writes in the console? (a) if (b) console.log() (c) alert() (d) let
9. 9.⚡ What does this code print? (Look at the quotes!)
   let x = "2";
   let y = 3;
   console.log(x + y); (a) 23 (b) 5 (c) Error
10. 10.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 8;
    console.log(x + y); (a) Error (b) 68 (c) 14
11. 11.⚡ What does this code show?
    let name = "Zoya";
    console.log("Welcome, " + name + "!"); (a) name (b) Welcome, Zoya! (c) Zoya (d) Welcome, name!
12. 12.⚡ Which JavaScript word shows a pop-up box? (a) let (b) alert() (c) console.log() (d) for
13. 13.⚡ What number does this code print?
    let a = 49;
    let b = 20;
    console.log(a - b);
14. 14.⚡ Which JavaScript word repeats code? (a) for (b) alert() (c) let (d) console.log()
15. 15.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 9;
    console.log(x + y); (a) 13 (b) 49 (c) Error
16. 16.⚡ Which JavaScript word runs code when true? (a) if (b) console.log() (c) let (d) alert()
17. 17.⚡ What number does this code print?
    let books = 29;
    books = books + 11;
    books = books - 6;
    console.log(books);
18. 18.⚡ What number does this code print?
    let a = 40;
    let b = 31;
    console.log(a + b);
19. 19.⚡ What does alert() show? (a) a new tab (b) a pop-up box (c) a table (d) a picture
20. 20.⚡ What number does this code print?
    let apples = 5;
    apples = apples + 7;
    apples = apples - 1;
    console.log(apples);
21. 21.⚡ What number does this code print?
    let apples = 18;
    apples = apples + 17;
    apples = apples - 35;
    console.log(apples);
22. 22.⚡ What number does this code print?
    let a = 42;
    let b = 2;
    console.log(a + b);
23. 23.⚡ What does this code show?
    let name = "Kabir";
    alert("Well done, " + name + "!"); (a) Kabir (b) Well done, Kabir! (c) Well done, name! (d) name
24. 24.⚡ What number does this code print?
    let a = 8;
    let b = 5;
    console.log(a * b);
25. 25.⚡ What number does this code print?
    let a = 25;
    let b = 23;
    console.log(a - b);
26. 26.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 8;
    console.log(x + y); (a) Error (b) 9 (c) 18
27. 27.⚡ What number does this code print?
    let score = 19;
    score = score + 16;
    score = score - 32;
    console.log(score);
28. 28.⚡ What number does this code print?
    let marks = 21;
    marks = marks + 3;
    marks = marks - 5;
    console.log(marks);
29. 29.⚡ What number does this code print?
    let a = 47;
    let b = 40;
    console.log(a + b);
30. 30.⚡ What does this code show?
    let name = "Arjun";
    console.log("Well done, " + name + "!"); (a) Well done, name! (b) Well done, Arjun! (c) name (d) Arjun
31. 31.⚡ What number does this code print?
    let a = 42;
    let b = 11;
    console.log(a - b);
32. 32.⚡ What does this code show?
    let name = "Kabir";
    alert("Welcome, " + name + "!"); (a) Welcome, name! (b) Kabir (c) Welcome, Kabir! (d) name
33. 33.⚡ What number does this code print?
    let marks = 23;
    marks = marks + 4;
    marks = marks - 13;
    console.log(marks);
34. 34.⚡ What number does this code print?
    let a = 12;
    let b = 9;
    console.log(a - b);
35. 35.⚡ What does this code show?
    let name = "Riya";
    console.log("Hi, " + name + "!"); (a) Hi, name! (b) name (c) Riya (d) Hi, Riya!
36. 36.⚡ What does this code show?
    let name = "Kabir";
    console.log("Well done, " + name + "!"); (a) Well done, name! (b) Well done, Kabir! (c) Kabir (d) name
37. 37.⚡ What does this code show?
    let name = "Zoya";
    console.log("Well done, " + name + "!"); (a) name (b) Zoya (c) Well done, Zoya! (d) Well done, name!
38. 38.⚡ What number does this code print?
    let marks = 8;
    marks = marks + 2;
    marks = marks - 8;
    console.log(marks);
39. 39.⚡ What number does this code print?
    let books = 29;
    books = books + 18;
    books = books - 36;
    console.log(books);
40. 40.⚡ A JavaScript file usually ends with which extension? (a) .html (b) .js (c) .jpg (d) .css

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