App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 467 · 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.💾 pop() takes off the last item. What does this code show?
   let friends = ["Zoya", "Riya", "Kabir"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Zoya (b) Kabir (c) Riya
2. 2.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) a draft you are typing (d) photos on two devices
3. 3.💾 What does this code show? (Positions start at 0.)
   let songs = ["Stars", "Sunrise", "Monsoon"];
   show(songs[0]); (a) Sunrise (b) Stars (c) Monsoon
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.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
6. 6.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
7. 7.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
8. 8.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) never need a password (c) use it on any device (d) skip the internet
9. 9.💾 What number does this code show?
   let friends = ["Aman", "Zoya", "Meera"];
   friends.push("Kabir");
   friends.push("Riya");
   show(friends.length);
10. 10.💾 What number does this code show?
    let notes = ["Sports", "Hindi", "Music"];
    notes.push("Maths");
    notes.push("Science");
    show(notes.length);
11. 11.💾 Which can hold many values in order? (a) a single number (b) a list (c) a switch (d) a button
12. 12.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
13. 13.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
14. 14.💾 What number does this code show?
    let score = 3;
    score = score - 1;
    score = score + 4;
    show(score);
15. 15.💾 What number does this code show?
    let notes = ["Science", "Art", "Music", "Sports"];
    notes.push("Hindi");
    show(notes.length);
16. 16.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Kites", "Sunrise"];
    show(songs[2]); (a) Kites (b) Sunrise (c) Stars
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 notes = ["Hindi", "Art", "Maths"];
    notes.push("Music");
    notes.push("Science");
    show(notes.length);
19. 19.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
20. 20.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
21. 21.💾 What number does this code show?
    let songs = ["Kites", "Monsoon"];
    songs.push("Rain");
    songs.push("Stars");
    show(songs.length);
22. 22.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Music", "Hindi"];
    show(notes[2]); (a) Music (b) Art (c) Hindi
23. 23.Which of these fits saving on the phone? (a) a class leaderboard (b) the sound on/off setting (c) a shared to-do list (d) chat messages to friends
24. 24.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
25. 25.💾 What number does this code show?
    let stars = 7;
    stars = stars - 1;
    stars = stars + 5;
    show(stars);
26. 26.Which of these fits saving in the cloud? (a) your last game level (b) a draft you are typing (c) notes to read offline (d) a shared to-do list
27. 27.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Kites", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Monsoon (c) Kites
28. 28.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Sports", "Hindi", "Science"];
    show(notes[0]); (a) Hindi (b) Sports (c) Science (d) Art
29. 29.💾 What number does this code show?
    let notes = ["Music", "Science", "Maths", "Art"];
    notes.push("Hindi");
    notes.push("Sports");
    show(notes.length);
30. 30.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Meera", "Zoya"];
    show(friends[2]); (a) Zoya (b) Aman (c) Meera
31. 31.💾 What number does this code show?
    let songs = ["Ocean", "Stars"];
    songs.push("Rain");
    show(songs.length);
32. 32.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Stars", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Stars (c) Rain
33. 33.💾 Which works with no internet at all? (a) a cloud leaderboard (b) data saved on the phone (c) a shared chat (d) a cloud backup
34. 34.💾 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
35. 35.💾 What number does this code show?
    let notes = ["Maths", "Art", "Sports"];
    notes.push("Music");
    notes.push("Hindi");
    show(notes.length);
36. 36.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Sunrise", "Kites", "Ocean", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Sunrise (c) Kites (d) Rain
37. 37.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
38. 38.💾 What number does this code show?
    let coins = 4;
    coins = coins - 1;
    coins = coins + 3;
    show(coins);
39. 39.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
40. 40.Which of these fits saving on the phone? (a) a shared to-do list (b) your last game level (c) chat messages to friends (d) a class leaderboard

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