App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 779 · 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.True or false: notes to read offline fits saving on the phone. (a) False (b) True
2. 2.💾 pop() takes off the last item. What does this code show?
   let friends = ["Arjun", "Kabir", "Meera"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Arjun (b) Meera (c) Kabir
3. 3.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) a shared to-do list (d) the sound on/off setting
4. 4.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
5. 5.💾 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
6. 6.💾 What does this code show? (Positions start at 0.)
   let notes = ["Sports", "Art", "Hindi", "Music"];
   show(notes[1]); (a) Sports (b) Art (c) Music (d) Hindi
7. 7.Which of these fits saving in the cloud? (a) a shared to-do list (b) your last game level (c) notes to read offline (d) the sound on/off setting
8. 8.💾 What number does this code show?
   let songs = ["Kites", "Sunrise"];
   songs.push("Rain");
   show(songs.length);
9. 9.💾 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
10. 10.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
11. 11.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
12. 12.💾 Which can hold many values in order? (a) a list (b) a switch (c) a button (d) a single number
13. 13.💾 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
14. 14.💾 What number does this code show?
    let notes = ["Sports", "Music", "Hindi"];
    notes.push("Science");
    notes.push("Art");
    show(notes.length);
15. 15.💾 Which works with no internet at all? (a) data saved on the phone (b) a shared chat (c) a cloud leaderboard (d) a cloud backup
16. 16.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
17. 17.True or false: photos on two devices fits saving on the phone. (a) False (b) True
18. 18.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Arjun", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Arjun (c) Riya
19. 19.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
20. 20.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Maths", "Hindi"];
    show(notes[1]); (a) Maths (b) Hindi (c) Science
21. 21.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
22. 22.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Riya", "Aman", "Arjun"];
    show(friends[3]); (a) Aman (b) Riya (c) Arjun (d) Meera
23. 23.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a draft you are typing (c) chat messages to friends (d) notes to read offline
24. 24.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
25. 25.True or false: your last game level fits saving on the phone. (a) False (b) True
26. 26.💾 What number does this code show?
    let songs = ["Rain", "Stars", "Kites", "Monsoon"];
    songs.push("Sunrise");
    show(songs.length);
27. 27.💾 What number does this code show?
    let lives = 8;
    lives = lives - 6;
    lives = lives + 5;
    show(lives);
28. 28.Which of these fits saving on the phone? (a) a shared to-do list (b) photos on two devices (c) chat messages to friends (d) a draft you are typing
29. 29.💾 What is a variable? (a) a phone setting (b) a named box for a value (c) a type of screen (d) a picture
30. 30.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Arjun", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Meera (b) Arjun (c) Kabir
31. 31.💾 What number does this code show?
    let stars = 4;
    stars = stars - 3;
    stars = stars + 4;
    show(stars);
32. 32.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) photos on two devices (d) the sound on/off setting
33. 33.💾 What number does this code show?
    let score = 4;
    score = score - 1;
    score = score + 5;
    show(score);
34. 34.💾 What number does this code show?
    let songs = ["Ocean", "Stars"];
    songs.push("Monsoon");
    songs.push("Rain");
    show(songs.length);
35. 35.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
36. 36.💾 What number does this code show?
    let songs = ["Rain", "Ocean"];
    songs.push("Stars");
    songs.push("Kites");
    show(songs.length);
37. 37.💾 What number does this code show?
    let lives = 7;
    lives = lives - 6;
    lives = lives + 3;
    show(lives);
38. 38.💾 What number does this code show?
    let points = 6;
    points = points - 2;
    points = points + 3;
    show(points);
39. 39.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 2 (c) 1 (d) 0
40. 40.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) a class leaderboard (d) notes to read offline

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