App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 660 · 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.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the screen turns off (c) the phone is lost (d) the app is closed
2. 2.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) a draft you are typing (d) photos on two devices
3. 3.True or false: your last game level fits saving in the cloud. (a) False (b) True
4. 4.💾 What number does this code show?
   let coins = 7;
   coins = coins - 2;
   coins = coins + 1;
   show(coins);
5. 5.💾 What number does this code show?
   let points = 7;
   points = points - 4;
   points = points + 3;
   show(points);
6. 6.Which of these fits saving in the cloud? (a) your last game level (b) a class leaderboard (c) a draft you are typing (d) the sound on/off setting
7. 7.💾 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
8. 8.Which of these fits saving on the phone? (a) the sound on/off setting (b) a shared to-do list (c) chat messages to friends (d) a class leaderboard
9. 9.💾 What number does this code show?
   let stars = 9;
   stars = stars - 8;
   stars = stars + 5;
   show(stars);
10. 10.💾 What number does this code show?
    let notes = ["Maths", "Art", "Science"];
    notes.push("Music");
    notes.push("Sports");
    show(notes.length);
11. 11.💾 What number does this code show?
    let coins = 9;
    coins = coins - 2;
    coins = coins + 4;
    show(coins);
12. 12.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Hindi", "Maths", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Sports (c) Maths (d) Hindi
13. 13.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) chat messages to friends
14. 14.💾 What is a variable? (a) a picture (b) a phone setting (c) a named box for a value (d) a type of screen
15. 15.True or false: your last game level fits saving on the phone. (a) False (b) True
16. 16.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
17. 17.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Science", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Art (c) Science
18. 18.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a list (d) a button
19. 19.💾 What number does this code show?
    let coins = 3;
    coins = coins - 3;
    coins = coins + 5;
    show(coins);
20. 20.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Music", "Hindi", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Music (c) Hindi (d) Sports
21. 21.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Science", "Sports"];
    show(notes[1]); (a) Science (b) Hindi (c) Sports
22. 22.💾 What number does this code show?
    let songs = ["Stars", "Ocean", "Kites", "Monsoon"];
    songs.push("Sunrise");
    show(songs.length);
23. 23.💾 What number does this code show?
    let lives = 8;
    lives = lives - 5;
    lives = lives + 1;
    show(lives);
24. 24.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
25. 25.💾 Which works with no internet at all? (a) a shared chat (b) data saved on the phone (c) a cloud leaderboard (d) a cloud backup
26. 26.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Science", "Sports"];
    show(notes[1]); (a) Sports (b) Art (c) Science
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 friends = ["Zoya", "Riya", "Meera", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Meera (b) Zoya (c) Riya (d) Aman
29. 29.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
30. 30.💾 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
31. 31.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Rain", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Sunrise (c) Ocean
32. 32.💾 What number does this code show?
    let stars = 5;
    stars = stars - 5;
    stars = stars + 3;
    show(stars);
33. 33.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Maths", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Hindi (c) Maths
34. 34.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Sunrise", "Stars", "Monsoon"];
    show(songs[3]); (a) Monsoon (b) Stars (c) Sunrise (d) Kites
35. 35.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 1 (c) 10 (d) 2
36. 36.💾 What number does this code show?
    let lives = 4;
    lives = lives - 2;
    lives = lives + 1;
    show(lives);
37. 37.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Maths", "Art"];
    show(notes[2]); (a) Maths (b) Art (c) Music
38. 38.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Music", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Sports (c) Music
39. 39.💾 What number does this code show?
    let score = 5;
    score = score - 1;
    score = score + 2;
    show(score);
40. 40.💾 What number does this code show?
    let songs = ["Stars", "Kites"];
    songs.push("Monsoon");
    show(songs.length);

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