App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 871 · 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 works with no internet at all? (a) data saved on the phone (b) a cloud leaderboard (c) a cloud backup (d) a shared chat
2. 2.💾 What does this code show? (Positions start at 0.)
   let notes = ["Sports", "Hindi", "Music", "Maths"];
   show(notes[3]); (a) Hindi (b) Sports (c) Maths (d) Music
3. 3.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) the sound on/off setting (d) photos on two devices
4. 4.Which of these fits saving on the phone? (a) a draft you are typing (b) chat messages to friends (c) a class leaderboard (d) photos on two devices
5. 5.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
6. 6.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
7. 7.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
8. 8.💾 What number does this code show?
   let coins = 3;
   coins = coins - 2;
   coins = coins + 5;
   show(coins);
9. 9.💾 What does this code show? (Positions start at 0.)
   let songs = ["Ocean", "Rain", "Kites", "Stars", "Monsoon"];
   show(songs[1]); (a) Stars (b) Rain (c) Ocean (d) Kites
10. 10.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
11. 11.💾 What number does this code show?
    let points = 5;
    points = points - 2;
    points = points + 5;
    show(points);
12. 12.💾 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
13. 13.Which of these fits saving in the cloud? (a) notes to read offline (b) your last game level (c) photos on two devices (d) the sound on/off setting
14. 14.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Ocean", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Ocean (c) Kites
15. 15.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
16. 16.💾 What number does this code show?
    let score = 4;
    score = score - 3;
    score = score + 5;
    show(score);
17. 17.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 0 (c) 10 (d) 2
18. 18.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Zoya", "Meera"];
    show(friends[0]); (a) Zoya (b) Meera (c) Riya
19. 19.💾 What number does this code show?
    let notes = ["Music", "Science", "Sports", "Hindi"];
    notes.push("Maths");
    show(notes.length);
20. 20.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
21. 21.💾 What number does this code show?
    let notes = ["Art", "Sports"];
    notes.push("Music");
    notes.push("Maths");
    show(notes.length);
22. 22.💾 What number does this code show?
    let friends = ["Meera", "Zoya"];
    friends.push("Arjun");
    friends.push("Aman");
    show(friends.length);
23. 23.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
24. 24.True or false: your last game level fits saving on the phone. (a) False (b) True
25. 25.💾 What number does this code show?
    let notes = ["Science", "Maths", "Art", "Music"];
    notes.push("Sports");
    notes.push("Hindi");
    show(notes.length);
26. 26.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
27. 27.💾 What number does this code show?
    let friends = ["Arjun", "Aman", "Riya"];
    friends.push("Zoya");
    friends.push("Meera");
    show(friends.length);
28. 28.💾 What number does this code show?
    let songs = ["Ocean", "Rain"];
    songs.push("Sunrise");
    songs.push("Monsoon");
    show(songs.length);
29. 29.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
30. 30.Which of these fits saving on the phone? (a) a shared to-do list (b) photos on two devices (c) your last game level (d) a class leaderboard
31. 31.💾 What number does this code show?
    let coins = 9;
    coins = coins - 5;
    coins = coins + 5;
    show(coins);
32. 32.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
33. 33.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Art", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Music (c) Sports
34. 34.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Riya", "Aman", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Meera (b) Kabir (c) Aman (d) Riya
35. 35.💾 What number does this code show?
    let friends = ["Riya", "Meera", "Arjun"];
    friends.push("Zoya");
    friends.push("Aman");
    show(friends.length);
36. 36.Which of these fits saving in the cloud? (a) a draft you are typing (b) a shared to-do list (c) notes to read offline (d) your last game level
37. 37.💾 What number does this code show?
    let notes = ["Science", "Music", "Art", "Hindi"];
    notes.push("Sports");
    show(notes.length);
38. 38.💾 Which can hold many values in order? (a) a button (b) a single number (c) a switch (d) a list
39. 39.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Stars", "Kites"];
    show(songs[2]); (a) Rain (b) Stars (c) Kites
40. 40.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) you send a message (c) the screen turns off (d) the app is closed

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