App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 116 · 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.Which of these fits saving in the cloud? (a) the sound on/off setting (b) chat messages to friends (c) notes to read offline (d) a draft you are typing
2. 2.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) notes to read offline (d) photos on two devices
3. 3.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
4. 4.💾 What does this code show? (Positions start at 0.)
   let friends = ["Arjun", "Riya", "Meera"];
   show(friends[0]); (a) Arjun (b) Riya (c) Meera
5. 5.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) a draft you are typing (d) photos on two devices
6. 6.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
7. 7.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) photos on two devices (d) the sound on/off setting
8. 8.💾 What does this code show? (Positions start at 0.)
   let friends = ["Zoya", "Riya", "Meera", "Kabir"];
   show(friends[1]); (a) Zoya (b) Kabir (c) Riya (d) Meera
9. 9.💾 What number does this code show?
   let friends = ["Aman", "Kabir", "Riya", "Arjun"];
   friends.push("Meera");
   friends.push("Zoya");
   show(friends.length);
10. 10.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Sunrise", "Rain"];
    show(songs[1]); (a) Kites (b) Rain (c) Sunrise
11. 11.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
12. 12.True or false: notes to read offline fits saving on the phone. (a) False (b) True
13. 13.💾 What number does this code show?
    let friends = ["Riya", "Meera", "Zoya"];
    friends.push("Arjun");
    friends.push("Aman");
    show(friends.length);
14. 14.💾 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
15. 15.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
16. 16.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
17. 17.💾 What number does this code show?
    let notes = ["Maths", "Sports"];
    notes.push("Music");
    show(notes.length);
18. 18.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Meera", "Kabir"];
    show(friends[1]); (a) Arjun (b) Kabir (c) Meera
19. 19.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 1 (c) 2 (d) 10
20. 20.💾 What number does this code show?
    let lives = 6;
    lives = lives - 2;
    lives = lives + 3;
    show(lives);
21. 21.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Arjun", "Aman"];
    show(friends[1]); (a) Riya (b) Aman (c) Arjun
22. 22.💾 What is a variable? (a) a type of screen (b) a picture (c) a named box for a value (d) a phone setting
23. 23.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
24. 24.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Ocean", "Monsoon", "Stars"];
    show(songs[1]); (a) Kites (b) Stars (c) Ocean (d) Monsoon
25. 25.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
26. 26.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) on the phone (b) in the cloud
27. 27.💾 What number does this code show?
    let coins = 6;
    coins = coins - 6;
    coins = coins + 5;
    show(coins);
28. 28.💾 What number does this code show?
    let stars = 4;
    stars = stars - 1;
    stars = stars + 1;
    show(stars);
29. 29.💾 What number does this code show?
    let songs = ["Stars", "Sunrise"];
    songs.push("Ocean");
    songs.push("Kites");
    show(songs.length);
30. 30.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the phone is lost (c) the app is closed (d) the screen turns off
31. 31.💾 What number does this code show?
    let stars = 5;
    stars = stars - 3;
    stars = stars + 2;
    show(stars);
32. 32.💾 What number does this code show?
    let score = 7;
    score = score - 2;
    score = score + 3;
    show(score);
33. 33.💾 What number does this code show?
    let songs = ["Stars", "Monsoon"];
    songs.push("Ocean");
    show(songs.length);
34. 34.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Meera", "Aman"];
    show(friends[0]); (a) Aman (b) Kabir (c) Meera
35. 35.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Rain", "Ocean", "Stars", "Kites"];
    show(songs[2]); (a) Rain (b) Monsoon (c) Ocean (d) Stars
36. 36.💾 What number does this code show?
    let notes = ["Art", "Sports", "Hindi", "Science"];
    notes.push("Maths");
    notes.push("Music");
    show(notes.length);
37. 37.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Sunrise", "Ocean"];
    show(songs[1]); (a) Sunrise (b) Ocean (c) Kites
38. 38.💾 Which works with no internet at all? (a) a cloud leaderboard (b) data saved on the phone (c) a shared chat (d) a cloud backup
39. 39.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
40. 40.💾 What number does this code show?
    let stars = 7;
    stars = stars - 1;
    stars = stars + 1;
    show(stars);

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