App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 977 · 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.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 2 (c) 10 (d) 0
2. 2.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
3. 3.💾 What number does this code show?
   let points = 4;
   points = points - 1;
   points = points + 3;
   show(points);
4. 4.💾 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
5. 5.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
6. 6.💾 What number does this code show?
   let friends = ["Zoya", "Riya", "Meera", "Arjun"];
   friends.push("Kabir");
   friends.push("Aman");
   show(friends.length);
7. 7.True or false: notes to read offline fits saving on the phone. (a) False (b) True
8. 8.💾 What number does this code show?
   let notes = ["Art", "Sports"];
   notes.push("Music");
   notes.push("Science");
   show(notes.length);
9. 9.Which of these fits saving on the phone? (a) photos on two devices (b) the sound on/off setting (c) chat messages to friends (d) a class leaderboard
10. 10.Which of these fits saving on the phone? (a) photos on two devices (b) a draft you are typing (c) a class leaderboard (d) a shared to-do list
11. 11.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
12. 12.💾 What number does this code show?
    let friends = ["Zoya", "Riya"];
    friends.push("Kabir");
    friends.push("Aman");
    show(friends.length);
13. 13.💾 What number does this code show?
    let coins = 5;
    coins = coins - 1;
    coins = coins + 3;
    show(coins);
14. 14.💾 What number does this code show?
    let songs = ["Monsoon", "Sunrise"];
    songs.push("Ocean");
    songs.push("Kites");
    show(songs.length);
15. 15.💾 What number does this code show?
    let songs = ["Sunrise", "Rain", "Stars", "Kites"];
    songs.push("Ocean");
    show(songs.length);
16. 16.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Zoya", "Kabir", "Aman", "Riya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Kabir (c) Arjun (d) Aman
17. 17.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
18. 18.💾 What number does this code show?
    let songs = ["Kites", "Sunrise", "Stars", "Ocean"];
    songs.push("Monsoon");
    songs.push("Rain");
    show(songs.length);
19. 19.💾 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
20. 20.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
21. 21.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
22. 22.True or false: your last game level fits saving in the cloud. (a) True (b) False
23. 23.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Meera", "Zoya", "Riya", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Meera (c) Aman (d) Riya
24. 24.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
25. 25.💾 What number does this code show?
    let friends = ["Kabir", "Zoya"];
    friends.push("Arjun");
    friends.push("Meera");
    show(friends.length);
26. 26.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Hindi", "Sports", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Hindi (c) Maths (d) Sports
27. 27.💾 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
28. 28.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Riya", "Zoya", "Meera", "Arjun"];
    show(friends[4]); (a) Zoya (b) Kabir (c) Riya (d) Arjun
29. 29.💾 Which can hold many values in order? (a) a single number (b) a button (c) a list (d) a switch
30. 30.Which of these fits saving in the cloud? (a) notes to read offline (b) photos on two devices (c) a draft you are typing (d) the sound on/off setting
31. 31.💾 What number does this code show?
    let notes = ["Science", "Sports"];
    notes.push("Art");
    notes.push("Maths");
    show(notes.length);
32. 32.Which of these fits saving in the cloud? (a) your last game level (b) a class leaderboard (c) the sound on/off setting (d) notes to read offline
33. 33.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Sports", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Maths (c) Sports
34. 34.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Monsoon", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Rain (c) Monsoon
35. 35.Which of these fits saving on the phone? (a) your last game level (b) a class leaderboard (c) photos on two devices (d) a shared to-do list
36. 36.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Sunrise", "Rain", "Ocean"];
    show(songs[1]); (a) Rain (b) Stars (c) Sunrise (d) Ocean
37. 37.💾 Saving data in the cloud lets you ___. (a) never need a password (b) shrink the app (c) skip the internet (d) use it on any device
38. 38.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Zoya", "Meera", "Aman", "Arjun"];
    show(friends[3]); (a) Riya (b) Meera (c) Zoya (d) Aman
39. 39.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
40. 40.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False

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