JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 303 · 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.⚡ What does this code print? (Look at the quotes!)
   let x = "4";
   let y = 3;
   console.log(x + y); (a) 7 (b) 43 (c) Error
2. 2.⚡ What does this code print? (Look at the quotes!)
   let x = "5";
   let y = 3;
   console.log(x + y); (a) 8 (b) 53 (c) Error
3. 3.⚡ Which JavaScript word shows a pop-up box? (a) for (b) let (c) console.log() (d) alert()
4. 4.⚡ What does alert() show? (a) a pop-up box (b) a picture (c) a table (d) a new tab
5. 5.⚡ What number does this code print?
   let a = 59;
   let b = 38;
   console.log(a + b);
6. 6.⚡ What does this code print? (Look at the quotes!)
   let x = "2";
   let y = 5;
   console.log(x + y); (a) 7 (b) 25 (c) Error
7. 7.⚡ Which word makes a new variable? (a) put (b) give (c) let (d) make
8. 8.⚡ Which JavaScript word makes a new variable? (a) if (b) console.log() (c) let (d) alert()
9. 9.⚡ What does this code print? (Look at the quotes!)
   let x = "5";
   let y = 2;
   console.log(x + y); (a) 52 (b) Error (c) 7
10. 10.⚡ What does this code show?
    let name = "Kabir";
    alert("Hi, " + name + "!"); (a) name (b) Hi, name! (c) Hi, Kabir! (d) Kabir
11. 11.⚡ Which JavaScript word repeats code? (a) console.log() (b) if (c) alert() (d) for
12. 12.⚡ What number does this code print?
    let marks = 16;
    marks = marks + 2;
    marks = marks - 17;
    console.log(marks);
13. 13.⚡ What does this code show?
    let name = "Arjun";
    console.log("Well done, " + name + "!"); (a) Well done, Arjun! (b) Arjun (c) name (d) Well done, name!
14. 14.⚡ Which JavaScript word writes in the console? (a) console.log() (b) alert() (c) if (d) for
15. 15.⚡ What number does this code print?
    let books = 8;
    books = books + 12;
    books = books - 9;
    console.log(books);
16. 16.⚡ What does this code show?
    let name = "Arjun";
    console.log("Hi, " + name + "!"); (a) name (b) Arjun (c) Hi, name! (d) Hi, Arjun!
17. 17.⚡ What number does this code print?
    let a = 12;
    let b = 5;
    console.log(a * b);
18. 18.⚡ What number does this code print?
    let a = 9;
    let b = 7;
    console.log(a * b);
19. 19.⚡ A JavaScript file usually ends with which extension? (a) .jpg (b) .html (c) .js (d) .css
20. 20.⚡ What number does this code print?
    let score = 6;
    score = score + 15;
    score = score - 8;
    console.log(score);
21. 21.⚡ What number does this code print?
    let a = 6;
    let b = 11;
    console.log(a * b);
22. 22.⚡ What does JavaScript add to a web page? (a) the page title (b) the domain name (c) only colours (d) actions and changes
23. 23.⚡ What number does this code print?
    let a = 24;
    let b = 1;
    console.log(a - b);
24. 24.⚡ What number does this code print?
    let a = 45;
    let b = 7;
    console.log(a + b);
25. 25.⚡ What number does this code print?
    let marks = 23;
    marks = marks + 8;
    marks = marks - 2;
    console.log(marks);
26. 26.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 4;
    console.log(x + y); (a) 9 (b) Error (c) 54
27. 27.⚡ What number does this code print?
    let a = 45;
    let b = 4;
    console.log(a + b);
28. 28.⚡ What number does this code print?
    let coins = 10;
    coins = coins + 2;
    coins = coins - 11;
    console.log(coins);
29. 29.⚡ Which tag holds JavaScript in a page? (a) <js> (b) <script> (c) <code> (d) <style>
30. 30.⚡ What does this code show?
    let name = "Riya";
    alert("Hello, " + name + "!"); (a) Hello, Riya! (b) Hello, name! (c) Riya (d) name
31. 31.⚡ What number does this code print?
    let a = 9;
    let b = 2;
    console.log(a + b);
32. 32.⚡ What number does this code print?
    let a = 2;
    let b = 3;
    console.log(a * b);
33. 33.⚡ What number does this code print?
    let apples = 22;
    apples = apples + 2;
    apples = apples - 5;
    console.log(apples);
34. 34.⚡ Which JavaScript word runs code when true? (a) if (b) alert() (c) console.log() (d) for
35. 35.⚡ What number does this code print?
    let a = 47;
    let b = 17;
    console.log(a + b);
36. 36.⚡ What number does this code print?
    let a = 4;
    let b = 6;
    console.log(a * b);
37. 37.⚡ Where does console.log() show its output? (a) in the address bar (b) in the console (c) on the title bar (d) on the printer
38. 38.⚡ What number does this code print?
    let a = 33;
    let b = 10;
    console.log(a + b);
39. 39.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 7;
    console.log(x + y); (a) 9 (b) 27 (c) Error
40. 40.⚡ What does this code show?
    let name = "Riya";
    alert("Welcome, " + name + "!"); (a) Welcome, Riya! (b) Welcome, name! (c) Riya (d) name

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