App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 940 · 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 photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
2. 2.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
3. 3.💾 What number does this code show?
   let lives = 8;
   lives = lives - 8;
   lives = lives + 3;
   show(lives);
4. 4.💾 What number does this code show?
   let notes = ["Sports", "Science", "Art", "Music"];
   notes.push("Hindi");
   show(notes.length);
5. 5.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
6. 6.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
7. 7.💾 pop() takes off the last item. What does this code show?
   let notes = ["Art", "Science", "Hindi", "Music"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Art (b) Science (c) Hindi (d) Music
8. 8.💾 What number does this code show?
   let songs = ["Ocean", "Stars", "Sunrise", "Rain"];
   songs.push("Kites");
   show(songs.length);
9. 9.💾 What does this code show? (Positions start at 0.)
   let notes = ["Art", "Maths", "Music", "Science"];
   show(notes[2]); (a) Maths (b) Science (c) Art (d) Music
10. 10.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
11. 11.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Zoya", "Kabir", "Arjun", "Meera"];
    show(friends[3]); (a) Kabir (b) Arjun (c) Aman (d) Zoya
12. 12.💾 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
13. 13.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) the phone is lost (c) the screen turns off (d) you send a message
14. 14.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
15. 15.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Zoya", "Riya", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Kabir (c) Zoya (d) Riya
16. 16.💾 What number does this code show?
    let songs = ["Rain", "Sunrise", "Monsoon"];
    songs.push("Ocean");
    show(songs.length);
17. 17.💾 Which can hold many values in order? (a) a list (b) a single number (c) a switch (d) a button
18. 18.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
19. 19.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a shared to-do list (d) the sound on/off setting
20. 20.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
21. 21.💾 What is a variable? (a) a picture (b) a named box for a value (c) a phone setting (d) a type of screen
22. 22.💾 Which works with no internet at all? (a) data saved on the phone (b) a cloud backup (c) a cloud leaderboard (d) a shared chat
23. 23.💾 What number does this code show?
    let friends = ["Zoya", "Aman", "Kabir", "Arjun"];
    friends.push("Meera");
    friends.push("Riya");
    show(friends.length);
24. 24.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Maths", "Music", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Music (c) Maths (d) Art
25. 25.💾 What number does this code show?
    let coins = 8;
    coins = coins - 8;
    coins = coins + 2;
    show(coins);
26. 26.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Maths", "Sports", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Hindi (c) Maths (d) Science
27. 27.💾 What number does this code show?
    let friends = ["Riya", "Zoya"];
    friends.push("Arjun");
    show(friends.length);
28. 28.💾 Saving data in the cloud lets you ___. (a) use it on any device (b) never need a password (c) shrink the app (d) skip the internet
29. 29.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Sunrise", "Stars", "Kites"];
    show(songs[0]); (a) Stars (b) Kites (c) Rain (d) Sunrise
30. 30.Which of these fits saving in the cloud? (a) photos on two devices (b) the sound on/off setting (c) your last game level (d) notes to read offline
31. 31.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) a class leaderboard
32. 32.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
33. 33.💾 What number does this code show?
    let score = 7;
    score = score - 1;
    score = score + 3;
    show(score);
34. 34.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) a draft you are typing (d) photos on two devices
35. 35.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Zoya", "Aman", "Meera", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Riya (c) Meera (d) Zoya
36. 36.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
37. 37.💾 What number does this code show?
    let friends = ["Zoya", "Kabir", "Meera"];
    friends.push("Aman");
    friends.push("Riya");
    show(friends.length);
38. 38.💾 What number does this code show?
    let friends = ["Zoya", "Kabir"];
    friends.push("Aman");
    show(friends.length);
39. 39.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
40. 40.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Aman", "Kabir"];
    show(friends[0]); (a) Aman (b) Riya (c) Kabir

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