App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 153 · 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 songs = ["Rain", "Kites", "Ocean", "Monsoon", "Sunrise"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Kites (b) Monsoon (c) Ocean (d) Rain
3. 3.💾 What number does this code show?
   let points = 9;
   points = points - 9;
   points = points + 1;
   show(points);
4. 4.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
5. 5.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
6. 6.💾 What is a variable? (a) a named box for a value (b) a picture (c) a type of screen (d) a phone setting
7. 7.💾 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
8. 8.💾 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
9. 9.💾 pop() takes off the last item. What does this code show?
   let notes = ["Art", "Hindi", "Science", "Music"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Science (b) Music (c) Art (d) Hindi
10. 10.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
11. 11.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
12. 12.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Rain", "Ocean", "Sunrise", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Rain (c) Ocean (d) Sunrise
13. 13.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Meera", "Arjun"];
    show(friends[2]); (a) Meera (b) Arjun (c) Aman
14. 14.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) chat messages to friends (d) notes to read offline
15. 15.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
16. 16.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Riya", "Meera", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Meera (c) Kabir (d) Zoya
17. 17.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) a draft you are typing (d) a shared to-do list
18. 18.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Art", "Sports", "Music"];
    show(notes[0]); (a) Maths (b) Sports (c) Music (d) Art
19. 19.Which of these fits saving in the cloud? (a) photos on two devices (b) the sound on/off setting (c) your last game level (d) notes to read offline
20. 20.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Art", "Maths"];
    show(notes[1]); (a) Maths (b) Art (c) Hindi
21. 21.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Kabir", "Aman", "Arjun"];
    show(friends[1]); (a) Arjun (b) Kabir (c) Aman (d) Meera
22. 22.💾 Which works with no internet at all? (a) a cloud backup (b) data saved on the phone (c) a cloud leaderboard (d) a shared chat
23. 23.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
24. 24.💾 What number does this code show?
    let songs = ["Kites", "Monsoon"];
    songs.push("Ocean");
    show(songs.length);
25. 25.Which of these fits saving on the phone? (a) photos on two devices (b) a class leaderboard (c) a shared to-do list (d) the sound on/off setting
26. 26.True or false: your last game level fits saving in the cloud. (a) False (b) True
27. 27.💾 What number does this code show?
    let notes = ["Music", "Maths"];
    notes.push("Art");
    show(notes.length);
28. 28.💾 In most code, the first item of a list is at position ___. (a) 2 (b) 0 (c) 10 (d) 1
29. 29.Which of these fits saving in the cloud? (a) your last game level (b) chat messages to friends (c) notes to read offline (d) a draft you are typing
30. 30.💾 Which can hold many values in order? (a) a button (b) a switch (c) a list (d) a single number
31. 31.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
32. 32.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) the app is closed (c) the screen turns off (d) you send a message
33. 33.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Stars", "Sunrise", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Sunrise (c) Stars (d) Rain
34. 34.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Ocean", "Kites", "Rain", "Sunrise"];
    show(songs[0]); (a) Ocean (b) Rain (c) Stars (d) Kites
35. 35.True or false: your last game level fits saving on the phone. (a) False (b) True
36. 36.💾 What number does this code show?
    let friends = ["Aman", "Kabir", "Meera", "Zoya"];
    friends.push("Arjun");
    show(friends.length);
37. 37.💾 What number does this code show?
    let lives = 5;
    lives = lives - 2;
    lives = lives + 3;
    show(lives);
38. 38.💾 What number does this code show?
    let score = 4;
    score = score - 3;
    score = score + 4;
    show(score);
39. 39.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Riya", "Aman"];
    show(friends[1]); (a) Kabir (b) Riya (c) Aman
40. 40.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Science", "Art", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Sports (c) Science (d) Art

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