App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 758 · 40 questions

Developer's tip (Box, list, place): A variable holds one value; a list holds many in order. Positions start at 0. push adds to the end; pop takes off the last item; length is how many items. On the phone: works offline, private. In the cloud: shared, any device, needs the internet.

1. 1.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
2. 2.💾 What does this code show? (Positions start at 0.)
   let notes = ["Sports", "Maths", "Hindi"];
   show(notes[2]); (a) Sports (b) Maths (c) Hindi
3. 3.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
4. 4.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
5. 5.💾 What number does this code show?
   let songs = ["Ocean", "Monsoon", "Rain"];
   songs.push("Kites");
   show(songs.length);
6. 6.💾 pop() takes off the last item. What does this code show?
   let friends = ["Riya", "Kabir", "Zoya", "Meera", "Arjun"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Kabir (b) Riya (c) Meera (d) Zoya
7. 7.💾 What number does this code show?
   let points = 4;
   points = points - 4;
   points = points + 1;
   show(points);
8. 8.💾 What number does this code show?
   let lives = 6;
   lives = lives - 5;
   lives = lives + 1;
   show(lives);
9. 9.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) on the phone (b) in the cloud
10. 10.💾 What number does this code show?
    let notes = ["Music", "Science", "Art"];
    notes.push("Maths");
    show(notes.length);
11. 11.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
12. 12.Which of these fits saving in the cloud? (a) chat messages to friends (b) a draft you are typing (c) your last game level (d) notes to read offline
13. 13.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a cloud backup (c) data saved on the phone (d) a shared chat
14. 14.💾 What number does this code show?
    let songs = ["Ocean", "Rain"];
    songs.push("Sunrise");
    songs.push("Monsoon");
    show(songs.length);
15. 15.💾 What number does this code show?
    let stars = 4;
    stars = stars - 3;
    stars = stars + 3;
    show(stars);
16. 16.💾 What number does this code show?
    let friends = ["Meera", "Aman", "Riya"];
    friends.push("Zoya");
    show(friends.length);
17. 17.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Kabir", "Meera", "Arjun"];
    show(friends[1]); (a) Meera (b) Riya (c) Arjun (d) Kabir
18. 18.💾 Which can hold many values in order? (a) a list (b) a single number (c) a switch (d) a button
19. 19.💾 What number does this code show?
    let notes = ["Art", "Science"];
    notes.push("Maths");
    show(notes.length);
20. 20.💾 What is a variable? (a) a picture (b) a type of screen (c) a phone setting (d) a named box for a value
21. 21.True or false: your last game level fits saving on the phone. (a) False (b) True
22. 22.💾 What number does this code show?
    let stars = 8;
    stars = stars - 7;
    stars = stars + 1;
    show(stars);
23. 23.Which of these fits saving on the phone? (a) chat messages to friends (b) your last game level (c) a shared to-do list (d) photos on two devices
24. 24.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Rain", "Stars", "Ocean"];
    show(songs[0]); (a) Stars (b) Ocean (c) Rain (d) Kites
25. 25.💾 What number does this code show?
    let songs = ["Kites", "Monsoon", "Stars"];
    songs.push("Ocean");
    show(songs.length);
26. 26.Which of these fits saving in the cloud? (a) notes to read offline (b) your last game level (c) the sound on/off setting (d) a class leaderboard
27. 27.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) on the phone (b) in the cloud
28. 28.💾 What number does this code show?
    let notes = ["Maths", "Sports", "Music", "Science"];
    notes.push("Art");
    notes.push("Hindi");
    show(notes.length);
29. 29.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 2 (c) 10 (d) 1
30. 30.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a class leaderboard (d) a draft you are typing
31. 31.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Science", "Sports"];
    show(notes[2]); (a) Art (b) Science (c) Sports
32. 32.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
33. 33.💾 What number does this code show?
    let lives = 7;
    lives = lives - 4;
    lives = lives + 3;
    show(lives);
34. 34.💾 What number does this code show?
    let notes = ["Maths", "Sports", "Music", "Art"];
    notes.push("Science");
    show(notes.length);
35. 35.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) in the cloud (b) on the phone
36. 36.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
37. 37.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Sunrise", "Kites", "Rain", "Ocean"];
    show(songs[3]); (a) Kites (b) Sunrise (c) Rain (d) Stars
38. 38.True or false: notes to read offline fits saving on the phone. (a) True (b) False
39. 39.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a shared to-do list (d) the sound on/off setting
40. 40.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Kites", "Stars", "Ocean", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Stars (c) Ocean (d) Kites

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