App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 757 · 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.💾 pop() takes off the last item. What does this code show?
   let notes = ["Music", "Hindi", "Sports", "Maths"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Hindi (b) Sports (c) Maths (d) Music
3. 3.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 2 (c) 10 (d) 0
4. 4.💾 pop() takes off the last item. What does this code show?
   let friends = ["Meera", "Riya", "Arjun"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Riya (b) Arjun (c) Meera
5. 5.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
6. 6.💾 What number does this code show?
   let notes = ["Art", "Maths", "Hindi"];
   notes.push("Sports");
   show(notes.length);
7. 7.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
8. 8.💾 What number does this code show?
   let score = 9;
   score = score - 2;
   score = score + 1;
   show(score);
9. 9.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
10. 10.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
11. 11.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
12. 12.Which of these fits saving in the cloud? (a) a draft you are typing (b) notes to read offline (c) photos on two devices (d) the sound on/off setting
13. 13.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
14. 14.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
15. 15.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) in the cloud (b) on the phone
16. 16.💾 Which can hold many values in order? (a) a switch (b) a button (c) a list (d) a single number
17. 17.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
18. 18.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Meera", "Aman"];
    show(friends[0]); (a) Meera (b) Aman (c) Kabir
19. 19.Which of these fits saving in the cloud? (a) the sound on/off setting (b) your last game level (c) a class leaderboard (d) a draft you are typing
20. 20.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Science", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Hindi (c) Maths
21. 21.💾 What is a variable? (a) a picture (b) a phone setting (c) a named box for a value (d) a type of screen
22. 22.True or false: your last game level fits saving in the cloud. (a) False (b) True
23. 23.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
24. 24.Which of these fits saving in the cloud? (a) a draft you are typing (b) your last game level (c) notes to read offline (d) chat messages to friends
25. 25.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Music", "Hindi"];
    show(notes[0]); (a) Art (b) Hindi (c) Music
26. 26.💾 Which works with no internet at all? (a) a cloud backup (b) a shared chat (c) a cloud leaderboard (d) data saved on the phone
27. 27.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
28. 28.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Music", "Maths", "Sports", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Hindi (c) Sports (d) Maths
29. 29.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Stars", "Kites", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Kites (c) Stars (d) Monsoon
30. 30.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
31. 31.💾 What number does this code show?
    let points = 6;
    points = points - 1;
    points = points + 4;
    show(points);
32. 32.Which of these fits saving in the cloud? (a) a shared to-do list (b) notes to read offline (c) a draft you are typing (d) your last game level
33. 33.💾 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
34. 34.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) you send a message (c) the screen turns off (d) the phone is lost
35. 35.💾 Saving data in the cloud lets you ___. (a) use it on any device (b) shrink the app (c) skip the internet (d) never need a password
36. 36.💾 What number does this code show?
    let coins = 3;
    coins = coins - 2;
    coins = coins + 2;
    show(coins);
37. 37.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Rain", "Monsoon"];
    show(songs[2]); (a) Rain (b) Sunrise (c) Monsoon
38. 38.💾 What number does this code show?
    let coins = 3;
    coins = coins - 2;
    coins = coins + 5;
    show(coins);
39. 39.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
40. 40.💾 What number does this code show?
    let notes = ["Science", "Music", "Hindi"];
    notes.push("Sports");
    show(notes.length);

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