App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 63 · 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 can hold many values in order? (a) a list (b) a single number (c) a switch (d) a button
2. 2.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
3. 3.Which of these fits saving in the cloud? (a) notes to read offline (b) your last game level (c) chat messages to friends (d) a draft you are typing
4. 4.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 0 (c) 1 (d) 2
5. 5.💾 What number does this code show?
   let friends = ["Meera", "Arjun"];
   friends.push("Riya");
   show(friends.length);
6. 6.💾 Which works with no internet at all? (a) a shared chat (b) a cloud leaderboard (c) data saved on the phone (d) a cloud backup
7. 7.💾 What number does this code show?
   let songs = ["Monsoon", "Ocean"];
   songs.push("Rain");
   songs.push("Sunrise");
   show(songs.length);
8. 8.True or false: photos on two devices fits saving on the phone. (a) False (b) True
9. 9.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
10. 10.💾 What is a variable? (a) a named box for a value (b) a type of screen (c) a phone setting (d) a picture
11. 11.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) on the phone (b) in the cloud
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 coins = 9;
    coins = coins - 6;
    coins = coins + 5;
    show(coins);
14. 14.💾 Saving data in the cloud lets you ___. (a) use it on any device (b) shrink the app (c) never need a password (d) skip the internet
15. 15.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
16. 16.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Stars", "Monsoon", "Rain", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Sunrise (c) Monsoon (d) Rain
17. 17.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) the screen turns off (c) you send a message (d) the app is closed
18. 18.💾 What number does this code show?
    let lives = 6;
    lives = lives - 1;
    lives = lives + 4;
    show(lives);
19. 19.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Maths", "Music"];
    show(notes[1]); (a) Maths (b) Art (c) Music
20. 20.💾 What number does this code show?
    let friends = ["Kabir", "Meera", "Riya"];
    friends.push("Zoya");
    friends.push("Arjun");
    show(friends.length);
21. 21.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
22. 22.💾 What number does this code show?
    let points = 8;
    points = points - 8;
    points = points + 3;
    show(points);
23. 23.💾 What number does this code show?
    let stars = 7;
    stars = stars - 2;
    stars = stars + 4;
    show(stars);
24. 24.💾 What number does this code show?
    let coins = 3;
    coins = coins - 2;
    coins = coins + 3;
    show(coins);
25. 25.Which of these fits saving on the phone? (a) notes to read offline (b) a class leaderboard (c) chat messages to friends (d) photos on two devices
26. 26.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
27. 27.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Art", "Music", "Sports"];
    show(notes[1]); (a) Music (b) Art (c) Hindi (d) Sports
28. 28.Which of these fits saving on the phone? (a) a shared to-do list (b) the sound on/off setting (c) chat messages to friends (d) photos on two devices
29. 29.💾 What number does this code show?
    let score = 3;
    score = score - 2;
    score = score + 4;
    show(score);
30. 30.💾 What number does this code show?
    let songs = ["Rain", "Stars", "Sunrise"];
    songs.push("Kites");
    show(songs.length);
31. 31.💾 What number does this code show?
    let points = 3;
    points = points - 2;
    points = points + 5;
    show(points);
32. 32.💾 What number does this code show?
    let stars = 7;
    stars = stars - 1;
    stars = stars + 1;
    show(stars);
33. 33.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Zoya", "Aman", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Kabir (c) Zoya (d) Aman
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 points = 3;
    points = points - 3;
    points = points + 2;
    show(points);
36. 36.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Monsoon", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Ocean (c) Monsoon
37. 37.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Art", "Hindi"];
    show(notes[0]); (a) Maths (b) Art (c) Hindi
38. 38.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
39. 39.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Stars", "Monsoon", "Sunrise", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Monsoon (c) Stars (d) Sunrise
40. 40.💾 What number does this code show?
    let points = 9;
    points = points - 2;
    points = points + 3;
    show(points);

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