App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 700 · 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 notes = ["Hindi", "Maths", "Music", "Art"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Hindi (b) Art (c) Maths (d) Music
2. 2.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
3. 3.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) a class leaderboard (d) your last game level
4. 4.💾 What does this code show? (Positions start at 0.)
   let notes = ["Sports", "Maths", "Art", "Hindi", "Science"];
   show(notes[2]); (a) Sports (b) Art (c) Maths (d) Hindi
5. 5.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
6. 6.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) never need a password (c) shrink the app (d) use it on any device
7. 7.💾 What does this code show? (Positions start at 0.)
   let friends = ["Riya", "Meera", "Kabir"];
   show(friends[1]); (a) Riya (b) Meera (c) Kabir
8. 8.💾 Which can hold many values in order? (a) a single number (b) a switch (c) a list (d) a button
9. 9.💾 What does this code show? (Positions start at 0.)
   let songs = ["Monsoon", "Ocean", "Stars"];
   show(songs[1]); (a) Stars (b) Ocean (c) Monsoon
10. 10.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 2 (c) 1 (d) 0
11. 11.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Science", "Music"];
    show(notes[0]); (a) Science (b) Maths (c) Music
12. 12.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the phone is lost (c) the screen turns off (d) the app is closed
13. 13.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Sports", "Art", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Sports (c) Science (d) Music
14. 14.💾 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
15. 15.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Meera", "Zoya", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Arjun (c) Meera (d) Zoya
16. 16.💾 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
17. 17.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
18. 18.💾 What number does this code show?
    let coins = 5;
    coins = coins - 1;
    coins = coins + 2;
    show(coins);
19. 19.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
20. 20.Which of these fits saving on the phone? (a) a shared to-do list (b) notes to read offline (c) a class leaderboard (d) photos on two devices
21. 21.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Music", "Science", "Sports"];
    show(notes[2]); (a) Music (b) Maths (c) Science (d) Sports
22. 22.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Zoya", "Arjun", "Kabir", "Riya"];
    show(friends[2]); (a) Arjun (b) Zoya (c) Kabir (d) Aman
23. 23.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
24. 24.True or false: your last game level fits saving on the phone. (a) True (b) False
25. 25.💾 Which works with no internet at all? (a) data saved on the phone (b) a shared chat (c) a cloud backup (d) a cloud leaderboard
26. 26.💾 What number does this code show?
    let songs = ["Monsoon", "Sunrise"];
    songs.push("Stars");
    songs.push("Rain");
    show(songs.length);
27. 27.💾 What is a variable? (a) a named box for a value (b) a picture (c) a type of screen (d) a phone setting
28. 28.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
29. 29.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Aman", "Kabir", "Meera"];
    show(friends[3]); (a) Zoya (b) Meera (c) Kabir (d) Aman
30. 30.💾 What number does this code show?
    let lives = 9;
    lives = lives - 8;
    lives = lives + 1;
    show(lives);
31. 31.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
32. 32.💾 What number does this code show?
    let lives = 8;
    lives = lives - 6;
    lives = lives + 1;
    show(lives);
33. 33.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) a draft you are typing (d) a shared to-do list
34. 34.💾 What number does this code show?
    let coins = 9;
    coins = coins - 1;
    coins = coins + 3;
    show(coins);
35. 35.💾 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
36. 36.Which of these fits saving on the phone? (a) photos on two devices (b) a draft you are typing (c) chat messages to friends (d) a shared to-do list
37. 37.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Art", "Hindi"];
    show(notes[2]); (a) Art (b) Sports (c) Hindi
38. 38.Which of these fits saving in the cloud? (a) your last game level (b) a draft you are typing (c) a class leaderboard (d) notes to read offline
39. 39.💾 What number does this code show?
    let friends = ["Meera", "Kabir", "Zoya", "Aman"];
    friends.push("Riya");
    friends.push("Arjun");
    show(friends.length);
40. 40.💾 What number does this code show?
    let songs = ["Rain", "Monsoon", "Kites"];
    songs.push("Stars");
    songs.push("Ocean");
    show(songs.length);

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