App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 890 · 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 a shared to-do list: on the phone or in the cloud? (a) in the cloud (b) on the phone
2. 2.💾 Saving data in the cloud lets you ___. (a) use it on any device (b) skip the internet (c) shrink the app (d) never need a password
3. 3.Which of these fits saving on the phone? (a) the sound on/off setting (b) photos on two devices (c) a class leaderboard (d) a shared to-do list
4. 4.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
5. 5.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
6. 6.💾 Which can hold many values in order? (a) a switch (b) a list (c) a button (d) a single number
7. 7.💾 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
8. 8.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) notes to read offline (d) chat messages to friends
9. 9.Which of these fits saving in the cloud? (a) chat messages to friends (b) the sound on/off setting (c) your last game level (d) a draft you are typing
10. 10.💾 What number does this code show?
    let friends = ["Aman", "Zoya"];
    friends.push("Meera");
    friends.push("Riya");
    show(friends.length);
11. 11.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Rain", "Stars", "Monsoon", "Sunrise"];
    show(songs[4]); (a) Sunrise (b) Rain (c) Stars (d) Kites
12. 12.Which of these fits saving on the phone? (a) photos on two devices (b) your last game level (c) a shared to-do list (d) a class leaderboard
13. 13.💾 What number does this code show?
    let notes = ["Maths", "Hindi", "Science"];
    notes.push("Sports");
    show(notes.length);
14. 14.💾 What number does this code show?
    let coins = 3;
    coins = coins - 1;
    coins = coins + 2;
    show(coins);
15. 15.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Music", "Science", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Sports (c) Art (d) Science
16. 16.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) a class leaderboard
17. 17.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
18. 18.💾 What number does this code show?
    let friends = ["Kabir", "Meera", "Aman"];
    friends.push("Zoya");
    show(friends.length);
19. 19.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) the phone is lost (c) the app is closed (d) you send a message
20. 20.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
21. 21.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Rain", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Rain (c) Ocean
22. 22.💾 Which works with no internet at all? (a) data saved on the phone (b) a shared chat (c) a cloud leaderboard (d) a cloud backup
23. 23.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Science", "Sports"];
    show(notes[0]); (a) Maths (b) Sports (c) Science
24. 24.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Art", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Art (c) Science
25. 25.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
26. 26.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) photos on two devices (d) a draft you are typing
27. 27.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
28. 28.💾 What number does this code show?
    let coins = 7;
    coins = coins - 2;
    coins = coins + 3;
    show(coins);
29. 29.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Riya", "Kabir", "Aman", "Zoya"];
    show(friends[4]); (a) Riya (b) Kabir (c) Zoya (d) Arjun
30. 30.💾 What number does this code show?
    let lives = 4;
    lives = lives - 2;
    lives = lives + 5;
    show(lives);
31. 31.💾 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
32. 32.💾 What number does this code show?
    let score = 8;
    score = score - 8;
    score = score + 4;
    show(score);
33. 33.💾 What number does this code show?
    let notes = ["Science", "Hindi"];
    notes.push("Sports");
    notes.push("Music");
    show(notes.length);
34. 34.💾 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) Aman (b) Zoya (c) Meera (d) Riya
35. 35.💾 What number does this code show?
    let stars = 5;
    stars = stars - 5;
    stars = stars + 3;
    show(stars);
36. 36.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
37. 37.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Maths", "Art"];
    show(notes[0]); (a) Hindi (b) Maths (c) Art
38. 38.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
39. 39.True or false: notes to read offline fits saving on the phone. (a) True (b) False
40. 40.💾 What number does this code show?
    let friends = ["Zoya", "Meera"];
    friends.push("Riya");
    friends.push("Arjun");
    show(friends.length);

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