JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 452 · 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.⚡ Which JavaScript word runs code when true? (a) console.log() (b) if (c) for (d) alert()
2. 2.⚡ Which JavaScript word makes a new variable? (a) alert() (b) console.log() (c) if (d) let
3. 3.⚡ What does JavaScript add to a web page? (a) actions and changes (b) the page title (c) only colours (d) the domain name
4. 4.⚡ Which JavaScript word shows a pop-up box? (a) alert() (b) let (c) if (d) console.log()
5. 5.⚡ Which word makes a new variable? (a) let (b) make (c) give (d) put
6. 6.⚡ What number does this code print?
   let score = 10;
   score = score + 20;
   score = score - 30;
   console.log(score);
7. 7.⚡ What does this code show?
   let name = "Arjun";
   alert("Well done, " + name + "!"); (a) Arjun (b) Well done, name! (c) Well done, Arjun! (d) name
8. 8.⚡ What does this code show?
   let name = "Arjun";
   alert("Welcome, " + name + "!"); (a) Welcome, Arjun! (b) Welcome, name! (c) Arjun (d) name
9. 9.⚡ A JavaScript file usually ends with which extension? (a) .html (b) .js (c) .css (d) .jpg
10. 10.⚡ What does this code show?
    let name = "Kabir";
    alert("Hi, " + name + "!"); (a) Kabir (b) Hi, name! (c) Hi, Kabir! (d) name
11. 11.⚡ What number does this code print?
    let a = 35;
    let b = 23;
    console.log(a - b);
12. 12.⚡ What number does this code print?
    let marks = 24;
    marks = marks + 10;
    marks = marks - 5;
    console.log(marks);
13. 13.⚡ Which JavaScript word repeats code? (a) for (b) console.log() (c) alert() (d) let
14. 14.⚡ What number does this code print?
    let marks = 23;
    marks = marks + 8;
    marks = marks - 18;
    console.log(marks);
15. 15.⚡ Which tag holds JavaScript in a page? (a) <script> (b) <js> (c) <style> (d) <code>
16. 16.⚡ What number does this code print?
    let a = 58;
    let b = 12;
    console.log(a + b);
17. 17.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 1;
    console.log(x + y); (a) 7 (b) Error (c) 61
18. 18.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 2;
    console.log(x + y); (a) 3 (b) 12 (c) Error
19. 19.⚡ Which JavaScript word writes in the console? (a) if (b) for (c) console.log() (d) alert()
20. 20.⚡ What number does this code print?
    let a = 38;
    let b = 16;
    console.log(a - b);
21. 21.⚡ What does this code show?
    let name = "Riya";
    alert("Welcome, " + name + "!"); (a) Welcome, name! (b) Riya (c) Welcome, Riya! (d) name
22. 22.⚡ What does this code show?
    let name = "Arjun";
    alert("Hi, " + name + "!"); (a) Hi, Arjun! (b) Hi, name! (c) name (d) Arjun
23. 23.⚡ What does this code show?
    let name = "Arjun";
    console.log("Welcome, " + name + "!"); (a) Welcome, Arjun! (b) name (c) Arjun (d) Welcome, name!
24. 24.⚡ What does this code show?
    let name = "Aman";
    console.log("Hi, " + name + "!"); (a) name (b) Hi, name! (c) Hi, Aman! (d) Aman
25. 25.⚡ What number does this code print?
    let a = 52;
    let b = 28;
    console.log(a - b);
26. 26.⚡ Where does console.log() show its output? (a) on the printer (b) on the title bar (c) in the console (d) in the address bar
27. 27.⚡ What number does this code print?
    let a = 17;
    let b = 5;
    console.log(a - b);
28. 28.⚡ What number does this code print?
    let marks = 23;
    marks = marks + 5;
    marks = marks - 7;
    console.log(marks);
29. 29.⚡ What does this code show?
    let name = "Zoya";
    alert("Hi, " + name + "!"); (a) Hi, name! (b) name (c) Zoya (d) Hi, Zoya!
30. 30.⚡ What number does this code print?
    let coins = 23;
    coins = coins + 5;
    coins = coins - 7;
    console.log(coins);
31. 31.⚡ What number does this code print?
    let coins = 11;
    coins = coins + 17;
    coins = coins - 10;
    console.log(coins);
32. 32.⚡ What number does this code print?
    let runs = 25;
    runs = runs + 3;
    runs = runs - 19;
    console.log(runs);
33. 33.⚡ What number does this code print?
    let coins = 20;
    coins = coins + 5;
    coins = coins - 10;
    console.log(coins);
34. 34.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 1;
    console.log(x + y); (a) 51 (b) 6 (c) Error
35. 35.⚡ What does this code show?
    let name = "Kabir";
    console.log("Welcome, " + name + "!"); (a) Welcome, Kabir! (b) Kabir (c) Welcome, name! (d) name
36. 36.⚡ What number does this code print?
    let a = 44;
    let b = 2;
    console.log(a + b);
37. 37.⚡ What number does this code print?
    let score = 19;
    score = score + 8;
    score = score - 15;
    console.log(score);
38. 38.⚡ What number does this code print?
    let runs = 30;
    runs = runs + 2;
    runs = runs - 3;
    console.log(runs);
39. 39.⚡ What number does this code print?
    let a = 24;
    let b = 15;
    console.log(a - b);
40. 40.⚡ What does alert() show? (a) a table (b) a pop-up box (c) a new tab (d) a picture

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