App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 421 · 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 draft you are typing: on the phone or in the cloud? (a) in the cloud (b) on the phone
2. 2.💾 Which can hold many values in order? (a) a switch (b) a list (c) a single number (d) a button
3. 3.Which of these fits saving in the cloud? (a) a draft you are typing (b) photos on two devices (c) your last game level (d) notes to read offline
4. 4.True or false: photos on two devices fits saving on the phone. (a) True (b) False
5. 5.💾 What does this code show? (Positions start at 0.)
   let songs = ["Ocean", "Monsoon", "Sunrise", "Kites"];
   show(songs[2]); (a) Kites (b) Ocean (c) Sunrise (d) Monsoon
6. 6.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
7. 7.💾 pop() takes off the last item. What does this code show?
   let songs = ["Sunrise", "Rain", "Ocean", "Stars"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Rain (b) Sunrise (c) Ocean (d) Stars
8. 8.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) photos on two devices (d) the sound on/off setting
9. 9.True or false: notes to read offline fits saving on the phone. (a) False (b) True
10. 10.💾 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
11. 11.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Music", "Hindi", "Art", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Music (c) Hindi (d) Art
12. 12.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
13. 13.💾 What number does this code show?
    let notes = ["Maths", "Sports"];
    notes.push("Music");
    show(notes.length);
14. 14.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 2 (c) 10 (d) 0
15. 15.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Sports", "Music"];
    show(notes[2]); (a) Sports (b) Science (c) Music
16. 16.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
17. 17.Which of these fits saving in the cloud? (a) chat messages to friends (b) a draft you are typing (c) the sound on/off setting (d) your last game level
18. 18.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Rain", "Monsoon"];
    show(songs[2]); (a) Stars (b) Monsoon (c) Rain
19. 19.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Sports", "Music", "Art", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Music (c) Art (d) Sports
20. 20.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) a class leaderboard (d) a draft you are typing
21. 21.💾 What number does this code show?
    let songs = ["Rain", "Stars", "Sunrise"];
    songs.push("Ocean");
    songs.push("Kites");
    show(songs.length);
22. 22.💾 What number does this code show?
    let coins = 4;
    coins = coins - 4;
    coins = coins + 1;
    show(coins);
23. 23.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
24. 24.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) photos on two devices (d) a draft you are typing
25. 25.💾 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
26. 26.💾 What number does this code show?
    let songs = ["Sunrise", "Ocean", "Monsoon", "Kites"];
    songs.push("Rain");
    show(songs.length);
27. 27.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
28. 28.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Stars", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Stars (c) Sunrise
29. 29.True or false: your last game level fits saving in the cloud. (a) True (b) False
30. 30.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Rain", "Ocean", "Monsoon", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Ocean (c) Kites (d) Monsoon
31. 31.Which of these fits saving on the phone? (a) a class leaderboard (b) notes to read offline (c) chat messages to friends (d) photos on two devices
32. 32.💾 What number does this code show?
    let friends = ["Aman", "Meera", "Riya"];
    friends.push("Arjun");
    show(friends.length);
33. 33.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Monsoon", "Stars", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Rain (c) Stars (d) Monsoon
34. 34.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
35. 35.💾 What number does this code show?
    let notes = ["Maths", "Sports", "Art"];
    notes.push("Science");
    show(notes.length);
36. 36.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Art", "Hindi", "Sports"];
    show(notes[2]); (a) Sports (b) Art (c) Science (d) Hindi
37. 37.💾 What number does this code show?
    let points = 6;
    points = points - 6;
    points = points + 2;
    show(points);
38. 38.💾 Saving data in the cloud lets you ___. (a) never need a password (b) shrink the app (c) skip the internet (d) use it on any device
39. 39.💾 What number does this code show?
    let score = 4;
    score = score - 2;
    score = score + 3;
    show(score);
40. 40.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Sports", "Science", "Hindi", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Science (c) Hindi (d) Maths

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