App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 721 · 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 of these fits saving on the phone? (a) photos on two devices (b) notes to read offline (c) a shared to-do list (d) a class leaderboard
2. 2.💾 Which can hold many values in order? (a) a switch (b) a button (c) a single number (d) a list
3. 3.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) use it on any device (c) never need a password (d) shrink the app
4. 4.Which of these fits saving on the phone? (a) a class leaderboard (b) your last game level (c) a shared to-do list (d) photos on two devices
5. 5.Which of these fits saving in the cloud? (a) your last game level (b) the sound on/off setting (c) notes to read offline (d) chat messages to friends
6. 6.💾 What does this code show? (Positions start at 0.)
   let friends = ["Meera", "Riya", "Kabir"];
   show(friends[2]); (a) Meera (b) Riya (c) Kabir
7. 7.💾 What does this code show? (Positions start at 0.)
   let songs = ["Kites", "Stars", "Monsoon"];
   show(songs[0]); (a) Stars (b) Monsoon (c) Kites
8. 8.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) your last game level (d) a shared to-do list
9. 9.💾 Which works with no internet at all? (a) a cloud backup (b) a cloud leaderboard (c) data saved on the phone (d) a shared chat
10. 10.💾 What number does this code show?
    let friends = ["Zoya", "Arjun"];
    friends.push("Meera");
    show(friends.length);
11. 11.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
12. 12.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 0 (c) 2 (d) 10
13. 13.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
14. 14.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Aman", "Riya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Riya (c) Arjun
15. 15.Which of these fits saving in the cloud? (a) photos on two devices (b) a draft you are typing (c) notes to read offline (d) the sound on/off setting
16. 16.True or false: your last game level fits saving on the phone. (a) False (b) True
17. 17.💾 What number does this code show?
    let points = 6;
    points = points - 6;
    points = points + 3;
    show(points);
18. 18.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) you send a message (c) the phone is lost (d) the app is closed
19. 19.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Hindi", "Maths", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Maths (c) Science (d) Hindi
20. 20.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Sports", "Science", "Maths", "Art"];
    show(notes[1]); (a) Sports (b) Science (c) Maths (d) Music
21. 21.💾 What number does this code show?
    let lives = 5;
    lives = lives - 5;
    lives = lives + 1;
    show(lives);
22. 22.💾 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
23. 23.💾 What number does this code show?
    let notes = ["Art", "Sports", "Science", "Maths"];
    notes.push("Music");
    notes.push("Hindi");
    show(notes.length);
24. 24.💾 What is a variable? (a) a phone setting (b) a named box for a value (c) a picture (d) a type of screen
25. 25.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
26. 26.💾 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
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.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Sunrise", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Rain (c) Sunrise
29. 29.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) photos on two devices (d) a draft you are typing
30. 30.💾 What number does this code show?
    let coins = 6;
    coins = coins - 4;
    coins = coins + 1;
    show(coins);
31. 31.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
32. 32.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Rain", "Stars"];
    show(songs[1]); (a) Monsoon (b) Rain (c) Stars
33. 33.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
34. 34.True or false: notes to read offline fits saving on the phone. (a) False (b) True
35. 35.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Rain", "Stars", "Ocean", "Monsoon"];
    show(songs[0]); (a) Rain (b) Sunrise (c) Ocean (d) Stars
36. 36.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Kites", "Monsoon", "Rain", "Stars"];
    show(songs[2]); (a) Sunrise (b) Rain (c) Kites (d) Monsoon
37. 37.Which of these fits saving in the cloud? (a) a class leaderboard (b) notes to read offline (c) the sound on/off setting (d) your last game level
38. 38.True or false: photos on two devices fits saving on the phone. (a) True (b) False
39. 39.💾 What number does this code show?
    let notes = ["Sports", "Maths", "Science"];
    notes.push("Music");
    notes.push("Art");
    show(notes.length);
40. 40.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Zoya", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Aman (c) Arjun

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