App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 966 · 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: a class leaderboard fits saving on the phone. (a) False (b) True
2. 2.💾 What number does this code show?
   let lives = 4;
   lives = lives - 3;
   lives = lives + 3;
   show(lives);
3. 3.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
4. 4.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
5. 5.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) chat messages to friends (d) the sound on/off setting
6. 6.💾 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
7. 7.True or false: photos on two devices fits saving on the phone. (a) True (b) False
8. 8.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a class leaderboard (d) your last game level
9. 9.💾 What does this code show? (Positions start at 0.)
   let notes = ["Music", "Art", "Sports", "Hindi", "Maths"];
   show(notes[1]); (a) Music (b) Art (c) Sports (d) Hindi
10. 10.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a list (d) a button
11. 11.True or false: notes to read offline fits saving on the phone. (a) True (b) False
12. 12.💾 What number does this code show?
    let friends = ["Meera", "Riya", "Kabir", "Zoya"];
    friends.push("Arjun");
    show(friends.length);
13. 13.💾 What number does this code show?
    let score = 3;
    score = score - 1;
    score = score + 3;
    show(score);
14. 14.💾 What number does this code show?
    let songs = ["Sunrise", "Rain", "Monsoon"];
    songs.push("Kites");
    songs.push("Stars");
    show(songs.length);
15. 15.Which of these fits saving in the cloud? (a) your last game level (b) a shared to-do list (c) notes to read offline (d) the sound on/off setting
16. 16.💾 What number does this code show?
    let stars = 5;
    stars = stars - 4;
    stars = stars + 4;
    show(stars);
17. 17.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
18. 18.💾 What number does this code show?
    let songs = ["Monsoon", "Sunrise", "Kites"];
    songs.push("Rain");
    songs.push("Stars");
    show(songs.length);
19. 19.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
20. 20.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) use it on any device (c) never need a password (d) skip the internet
21. 21.Which of these fits saving in the cloud? (a) your last game level (b) a class leaderboard (c) notes to read offline (d) the sound on/off setting
22. 22.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 10 (c) 2 (d) 1
23. 23.💾 What number does this code show?
    let stars = 8;
    stars = stars - 8;
    stars = stars + 5;
    show(stars);
24. 24.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Art", "Hindi"];
    show(notes[0]); (a) Maths (b) Art (c) Hindi
25. 25.💾 What number does this code show?
    let notes = ["Art", "Hindi", "Maths"];
    notes.push("Science");
    notes.push("Music");
    show(notes.length);
26. 26.💾 What is a variable? (a) a type of screen (b) a picture (c) a phone setting (d) a named box for a value
27. 27.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) chat messages to friends (d) notes to read offline
28. 28.💾 What number does this code show?
    let friends = ["Riya", "Arjun", "Meera"];
    friends.push("Aman");
    show(friends.length);
29. 29.Which of these fits saving in the cloud? (a) your last game level (b) the sound on/off setting (c) photos on two devices (d) notes to read offline
30. 30.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Art", "Sports", "Hindi", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Hindi (c) Art (d) Sports
31. 31.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Music", "Maths", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Maths (c) Music (d) Hindi
32. 32.💾 What number does this code show?
    let friends = ["Riya", "Meera", "Kabir", "Zoya"];
    friends.push("Arjun");
    friends.push("Aman");
    show(friends.length);
33. 33.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Art", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Maths (c) Science
34. 34.💾 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
35. 35.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) you send a message (c) the screen turns off (d) the app is closed
36. 36.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
37. 37.💾 What number does this code show?
    let coins = 8;
    coins = coins - 5;
    coins = coins + 2;
    show(coins);
38. 38.💾 What number does this code show?
    let coins = 6;
    coins = coins - 4;
    coins = coins + 3;
    show(coins);
39. 39.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Art", "Maths", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Art (c) Maths (d) Music
40. 40.True or false: photos on two devices fits saving in the cloud. (a) True (b) False

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