JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 835 · 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 number does this code print?
   let a = 9;
   let b = 11;
   console.log(a * b);
2. 2.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .jpg (c) .html (d) .js
3. 3.⚡ What number does this code print?
   let a = 2;
   let b = 2;
   console.log(a * b);
4. 4.⚡ What does alert() show? (a) a new tab (b) a table (c) a pop-up box (d) a picture
5. 5.⚡ What does this code print? (Look at the quotes!)
   let x = "1";
   let y = 4;
   console.log(x + y); (a) 5 (b) Error (c) 14
6. 6.⚡ Which JavaScript word repeats code? (a) alert() (b) if (c) for (d) let
7. 7.⚡ Which JavaScript word writes in the console? (a) let (b) for (c) if (d) console.log()
8. 8.⚡ What does JavaScript add to a web page? (a) only colours (b) the domain name (c) actions and changes (d) the page title
9. 9.⚡ What number does this code print?
   let a = 29;
   let b = 8;
   console.log(a - b);
10. 10.⚡ What number does this code print?
    let runs = 20;
    runs = runs + 6;
    runs = runs - 26;
    console.log(runs);
11. 11.⚡ Which word makes a new variable? (a) give (b) make (c) let (d) put
12. 12.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 5;
    console.log(x + y); (a) Error (b) 65 (c) 11
13. 13.⚡ What does this code show?
    let name = "Aman";
    alert("Hello, " + name + "!"); (a) Aman (b) Hello, Aman! (c) name (d) Hello, name!
14. 14.⚡ What number does this code print?
    let a = 49;
    let b = 39;
    console.log(a - b);
15. 15.⚡ Which tag holds JavaScript in a page? (a) <code> (b) <js> (c) <style> (d) <script>
16. 16.⚡ What does this code show?
    let name = "Aman";
    alert("Welcome, " + name + "!"); (a) Welcome, name! (b) Welcome, Aman! (c) Aman (d) name
17. 17.⚡ What number does this code print?
    let a = 43;
    let b = 36;
    console.log(a + b);
18. 18.⚡ What does this code show?
    let name = "Zoya";
    alert("Hello, " + name + "!"); (a) Zoya (b) Hello, name! (c) Hello, Zoya! (d) name
19. 19.⚡ Which JavaScript word shows a pop-up box? (a) let (b) alert() (c) if (d) for
20. 20.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 7;
    console.log(x + y); (a) 67 (b) Error (c) 13
21. 21.⚡ What number does this code print?
    let runs = 26;
    runs = runs + 3;
    runs = runs - 17;
    console.log(runs);
22. 22.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 9;
    console.log(x + y); (a) 39 (b) Error (c) 12
23. 23.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 1;
    console.log(x + y); (a) 2 (b) 11 (c) Error
24. 24.⚡ What does this code show?
    let name = "Meera";
    console.log("Welcome, " + name + "!"); (a) Meera (b) name (c) Welcome, Meera! (d) Welcome, name!
25. 25.⚡ What number does this code print?
    let a = 34;
    let b = 6;
    console.log(a - b);
26. 26.⚡ What number does this code print?
    let a = 33;
    let b = 31;
    console.log(a - b);
27. 27.⚡ Which JavaScript word makes a new variable? (a) for (b) console.log() (c) alert() (d) let
28. 28.⚡ Which JavaScript word runs code when true? (a) for (b) console.log() (c) if (d) alert()
29. 29.⚡ Where does console.log() show its output? (a) on the title bar (b) in the console (c) on the printer (d) in the address bar
30. 30.⚡ What number does this code print?
    let apples = 29;
    apples = apples + 17;
    apples = apples - 18;
    console.log(apples);
31. 31.⚡ What number does this code print?
    let apples = 21;
    apples = apples + 15;
    apples = apples - 35;
    console.log(apples);
32. 32.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 2;
    console.log(x + y); (a) Error (b) 9 (c) 72
33. 33.⚡ What number does this code print?
    let a = 59;
    let b = 22;
    console.log(a + b);
34. 34.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 7;
    console.log(x + y); (a) 97 (b) Error (c) 16
35. 35.⚡ What number does this code print?
    let runs = 29;
    runs = runs + 20;
    runs = runs - 1;
    console.log(runs);
36. 36.⚡ What number does this code print?
    let marks = 12;
    marks = marks + 6;
    marks = marks - 16;
    console.log(marks);
37. 37.⚡ What number does this code print?
    let a = 38;
    let b = 11;
    console.log(a + b);
38. 38.⚡ What does this code show?
    let name = "Arjun";
    alert("Well done, " + name + "!"); (a) Arjun (b) Well done, Arjun! (c) Well done, name! (d) name
39. 39.⚡ What does this code show?
    let name = "Kabir";
    console.log("Welcome, " + name + "!"); (a) Kabir (b) name (c) Welcome, name! (d) Welcome, Kabir!
40. 40.⚡ What does this code show?
    let name = "Arjun";
    console.log("Hi, " + name + "!"); (a) name (b) Hi, Arjun! (c) Arjun (d) Hi, name!

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