App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 461 · 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 notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
2. 2.💾 What does this code show? (Positions start at 0.)
   let notes = ["Hindi", "Maths", "Science", "Sports"];
   show(notes[0]); (a) Hindi (b) Sports (c) Maths (d) Science
3. 3.True or false: notes to read offline fits saving on the phone. (a) True (b) False
4. 4.💾 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
5. 5.💾 What does this code show? (Positions start at 0.)
   let notes = ["Sports", "Music", "Art", "Science", "Hindi"];
   show(notes[4]); (a) Sports (b) Art (c) Hindi (d) Music
6. 6.💾 What number does this code show?
   let lives = 3;
   lives = lives - 2;
   lives = lives + 2;
   show(lives);
7. 7.💾 What does this code show? (Positions start at 0.)
   let notes = ["Science", "Hindi", "Music", "Sports"];
   show(notes[3]); (a) Sports (b) Music (c) Science (d) Hindi
8. 8.💾 What number does this code show?
   let songs = ["Rain", "Sunrise"];
   songs.push("Stars");
   show(songs.length);
9. 9.💾 What does this code show? (Positions start at 0.)
   let songs = ["Rain", "Sunrise", "Ocean", "Monsoon", "Kites"];
   show(songs[3]); (a) Rain (b) Monsoon (c) Ocean (d) Sunrise
10. 10.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
11. 11.Which of these fits saving on the phone? (a) your last game level (b) chat messages to friends (c) a class leaderboard (d) a shared to-do list
12. 12.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) chat messages to friends (d) the sound on/off setting
13. 13.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a shared to-do list (c) a draft you are typing (d) notes to read offline
14. 14.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
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.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
17. 17.💾 What number does this code show?
    let score = 8;
    score = score - 8;
    score = score + 5;
    show(score);
18. 18.True or false: photos on two devices fits saving on the phone. (a) True (b) False
19. 19.💾 What number does this code show?
    let coins = 5;
    coins = coins - 1;
    coins = coins + 5;
    show(coins);
20. 20.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Ocean", "Rain", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Sunrise (c) Stars (d) Ocean
21. 21.💾 What number does this code show?
    let lives = 9;
    lives = lives - 4;
    lives = lives + 5;
    show(lives);
22. 22.Which of these fits saving in the cloud? (a) your last game level (b) a draft you are typing (c) the sound on/off setting (d) chat messages to friends
23. 23.💾 What number does this code show?
    let friends = ["Kabir", "Riya", "Zoya"];
    friends.push("Arjun");
    friends.push("Meera");
    show(friends.length);
24. 24.Which of these fits saving in the cloud? (a) notes to read offline (b) your last game level (c) a class leaderboard (d) a draft you are typing
25. 25.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a list (d) a button
26. 26.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
27. 27.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
28. 28.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Maths", "Music", "Science", "Hindi"];
    show(notes[2]); (a) Art (b) Science (c) Maths (d) Music
29. 29.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
30. 30.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Rain", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Rain (c) Ocean
31. 31.💾 What number does this code show?
    let friends = ["Kabir", "Aman"];
    friends.push("Riya");
    show(friends.length);
32. 32.💾 What number does this code show?
    let notes = ["Music", "Hindi", "Maths"];
    notes.push("Art");
    notes.push("Science");
    show(notes.length);
33. 33.💾 What number does this code show?
    let score = 3;
    score = score - 2;
    score = score + 2;
    show(score);
34. 34.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) skip the internet (c) never need a password (d) use it on any device
35. 35.💾 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
36. 36.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) a draft you are typing (d) a shared to-do list
37. 37.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 1 (c) 0 (d) 2
38. 38.True or false: your last game level fits saving in the cloud. (a) True (b) False
39. 39.💾 What number does this code show?
    let songs = ["Ocean", "Kites", "Rain", "Monsoon"];
    songs.push("Stars");
    show(songs.length);
40. 40.💾 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

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