App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 124 · 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 on the phone? (a) a draft you are typing (b) chat messages to friends (c) a shared to-do list (d) a class leaderboard
2. 2.💾 pop() takes off the last item. What does this code show?
   let notes = ["Hindi", "Science", "Sports", "Art"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Sports (b) Science (c) Art (d) Hindi
3. 3.💾 What number does this code show?
   let friends = ["Kabir", "Aman"];
   friends.push("Riya");
   friends.push("Arjun");
   show(friends.length);
4. 4.💾 pop() takes off the last item. What does this code show?
   let friends = ["Riya", "Aman", "Meera", "Zoya", "Kabir"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Riya (b) Meera (c) Zoya (d) Aman
5. 5.💾 Which works with no internet at all? (a) a cloud backup (b) a cloud leaderboard (c) a shared chat (d) data saved on the phone
6. 6.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
7. 7.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
8. 8.💾 In most code, the first item of a list is at position ___. (a) 2 (b) 10 (c) 0 (d) 1
9. 9.💾 Which can hold many values in order? (a) a button (b) a list (c) a single number (d) a switch
10. 10.Which of these fits saving on the phone? (a) notes to read offline (b) a class leaderboard (c) a shared to-do list (d) photos on two devices
11. 11.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Riya", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Kabir (c) Zoya
12. 12.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
13. 13.💾 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
14. 14.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Rain", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Stars (c) Rain
15. 15.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Riya", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Meera (b) Riya (c) Zoya
16. 16.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
17. 17.💾 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
18. 18.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
19. 19.Which of these fits saving on the phone? (a) photos on two devices (b) your last game level (c) a class leaderboard (d) chat messages to friends
20. 20.Which of these fits saving in the cloud? (a) chat messages to friends (b) notes to read offline (c) your last game level (d) a draft you are typing
21. 21.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
22. 22.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) a class leaderboard (d) your last game level
23. 23.💾 What number does this code show?
    let friends = ["Riya", "Aman", "Zoya", "Kabir"];
    friends.push("Arjun");
    show(friends.length);
24. 24.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
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.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
27. 27.💾 What number does this code show?
    let lives = 8;
    lives = lives - 3;
    lives = lives + 2;
    show(lives);
28. 28.💾 What number does this code show?
    let score = 3;
    score = score - 1;
    score = score + 5;
    show(score);
29. 29.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Art", "Science"];
    show(notes[2]); (a) Science (b) Music (c) Art
30. 30.💾 What is a variable? (a) a named box for a value (b) a phone setting (c) a picture (d) a type of screen
31. 31.💾 What number does this code show?
    let stars = 4;
    stars = stars - 3;
    stars = stars + 5;
    show(stars);
32. 32.💾 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
33. 33.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Art", "Maths", "Sports", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Maths (c) Sports (d) Art
34. 34.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Kabir", "Meera", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Zoya (c) Meera (d) Arjun
35. 35.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Kabir", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Kabir (c) Meera
36. 36.💾 What number does this code show?
    let coins = 9;
    coins = coins - 4;
    coins = coins + 1;
    show(coins);
37. 37.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Kites", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Rain (c) Kites
38. 38.💾 What number does this code show?
    let lives = 5;
    lives = lives - 4;
    lives = lives + 4;
    show(lives);
39. 39.💾 What number does this code show?
    let friends = ["Riya", "Arjun", "Aman"];
    friends.push("Meera");
    friends.push("Zoya");
    show(friends.length);
40. 40.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True

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