App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 983 · 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.💾 In most code, the first item of a list is at position ___. (a) 2 (b) 10 (c) 0 (d) 1
2. 2.Which of these fits saving on the phone? (a) your last game level (b) chat messages to friends (c) a shared to-do list (d) photos on two devices
3. 3.💾 What does this code show? (Positions start at 0.)
   let friends = ["Meera", "Riya", "Arjun", "Zoya", "Kabir"];
   show(friends[4]); (a) Meera (b) Kabir (c) Arjun (d) Riya
4. 4.💾 What number does this code show?
   let lives = 8;
   lives = lives - 3;
   lives = lives + 5;
   show(lives);
5. 5.💾 pop() takes off the last item. What does this code show?
   let songs = ["Stars", "Ocean", "Kites", "Rain"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Kites (b) Stars (c) Ocean (d) Rain
6. 6.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
7. 7.💾 What does this code show? (Positions start at 0.)
   let notes = ["Science", "Hindi", "Maths"];
   show(notes[2]); (a) Science (b) Hindi (c) Maths
8. 8.💾 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
9. 9.Which of these fits saving on the phone? (a) the sound on/off setting (b) chat messages to friends (c) a class leaderboard (d) photos on two devices
10. 10.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
11. 11.💾 What number does this code show?
    let friends = ["Riya", "Arjun"];
    friends.push("Meera");
    friends.push("Kabir");
    show(friends.length);
12. 12.True or false: your last game level fits saving on the phone. (a) False (b) True
13. 13.💾 What number does this code show?
    let score = 3;
    score = score - 1;
    score = score + 1;
    show(score);
14. 14.💾 Saving data in the cloud lets you ___. (a) never need a password (b) skip the internet (c) shrink the app (d) use it on any device
15. 15.True or false: notes to read offline fits saving on the phone. (a) False (b) True
16. 16.💾 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
17. 17.💾 What number does this code show?
    let songs = ["Rain", "Ocean", "Monsoon"];
    songs.push("Stars");
    songs.push("Sunrise");
    show(songs.length);
18. 18.💾 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
19. 19.💾 What number does this code show?
    let lives = 7;
    lives = lives - 5;
    lives = lives + 5;
    show(lives);
20. 20.💾 What number does this code show?
    let friends = ["Aman", "Arjun", "Zoya"];
    friends.push("Riya");
    show(friends.length);
21. 21.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
22. 22.💾 What number does this code show?
    let friends = ["Arjun", "Zoya", "Aman", "Kabir"];
    friends.push("Meera");
    friends.push("Riya");
    show(friends.length);
23. 23.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Riya", "Arjun", "Aman", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Aman (c) Kabir (d) Arjun
24. 24.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
25. 25.💾 What number does this code show?
    let coins = 5;
    coins = coins - 4;
    coins = coins + 5;
    show(coins);
26. 26.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
27. 27.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a class leaderboard (d) a draft you are typing
28. 28.Which of these fits saving in the cloud? (a) your last game level (b) a shared to-do list (c) the sound on/off setting (d) notes to read offline
29. 29.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a button (d) a list
30. 30.💾 What number does this code show?
    let songs = ["Ocean", "Kites", "Sunrise", "Rain"];
    songs.push("Stars");
    songs.push("Monsoon");
    show(songs.length);
31. 31.💾 What number does this code show?
    let score = 9;
    score = score - 7;
    score = score + 1;
    show(score);
32. 32.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a class leaderboard (c) your last game level (d) notes to read offline
33. 33.💾 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
34. 34.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the screen turns off (c) the app is closed (d) the phone is lost
35. 35.💾 What number does this code show?
    let score = 7;
    score = score - 7;
    score = score + 1;
    show(score);
36. 36.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Science", "Hindi", "Sports"];
    show(notes[3]); (a) Sports (b) Science (c) Art (d) Hindi
37. 37.💾 What number does this code show?
    let notes = ["Science", "Sports"];
    notes.push("Art");
    notes.push("Music");
    show(notes.length);
38. 38.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Riya", "Arjun", "Kabir", "Aman"];
    show(friends[4]); (a) Arjun (b) Aman (c) Riya (d) Zoya
39. 39.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Ocean", "Sunrise", "Kites", "Monsoon"];
    show(songs[0]); (a) Sunrise (b) Ocean (c) Kites (d) Rain
40. 40.💾 What number does this code show?
    let friends = ["Arjun", "Kabir"];
    friends.push("Aman");
    show(friends.length);

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