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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 167 · 40 questions
TalentJR

Developer's tip (Test, then choose): if (test) { A } else { B }: A runs when the test is true, B when it is false. else if: check from the top; the first true test wins and the rest are skipped. >= includes the number itself; > does not. === tests “is equal to”.

NameDateTime takenScore ___ / 40
  1. 1.🔀 Which badge does this quiz app show?
    let marks = 94;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  2. 2.🔀 Which badge does this quiz app show?
    let marks = 79;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  3. 3.🔀 What does this battery rule show?
    let battery = 8;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  4. 4.🔀 What does this sign-up rule show?
    let age = 13;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  5. 5.🔀 What number does this shop app show?
    let total = 290;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  6. 6.🔀 What does this sign-up rule show?
    let age = 17;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  7. 7.🔀 What does this sign-up rule show?
    let age = 14;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  8. 8.🔀 What does this sign-up rule show?
    let age = 8;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  9. 9.🔀 What does this battery rule show?
    let battery = 27;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  10. 10.🔀 With if / else if / else, how many parts run? (a) only one (b) all of them (c) none (d) two
  11. 11.🔀 When does the else part run? (a) when the test is true (b) always (c) never (d) when the test is false
  12. 12.🔀 In this course’s code, which sign tests “is equal to”? (a) !== (b) => (c) = (d) ===
  13. 13.🔀 What number does this shop app show?
    let total = 770;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  14. 14.🔀 What does this PIN rule show?
    let pin = "2610";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  15. 15.🔀 What does this PIN rule show?
    let pin = "5677";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  16. 16.🔀 What number does this shop app show?
    let total = 400;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  17. 17.🔀 What number does this shop app show?
    let total = 380;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  18. 18.🔀 What does this battery rule show?
    let battery = 74;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  19. 19.🔀 What does this PIN rule show?
    let pin = "3128";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  20. 20.🔀 What does if / else let an app do? (a) repeat forever (b) save a photo (c) pick one of two actions (d) draw a screen
  21. 21.🔀 What does this battery rule show?
    let battery = 45;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  22. 22.🔀 Which badge does this quiz app show?
    let marks = 48;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  23. 23.🔀 What number does this shop app show?
    let total = 890;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  24. 24.🔀 What number does this shop app show?
    let total = 370;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  25. 25.🔀 What does this battery rule show?
    let battery = 30;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  26. 26.🔀 What does this PIN rule show?
    let pin = "70172";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  27. 27.🔀 What does this sign-up rule show?
    let age = 12;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  28. 28.🔀 Which badge does this quiz app show?
    let marks = 53;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  29. 29.🔀 What number does this shop app show?
    let total = 330;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  30. 30.🔀 What does this PIN rule show?
    let pin = "188";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  31. 31.🔀 What does this sign-up rule show?
    let age = 9;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  32. 32.🔀 What number does this shop app show?
    let total = 820;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  33. 33.🔀 What does this PIN rule show?
    let pin = "854";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  34. 34.🔀 What does this sign-up rule show?
    let age = 10;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  35. 35.🔀 What does this PIN rule show?
    let pin = "61618";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  36. 36.🔀 Which badge does this quiz app show?
    let marks = 42;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  37. 37.🔀 What does this PIN rule show?
    let pin = "87726";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  38. 38.🔀 What number does this shop app show?
    let total = 870;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  39. 39.🔀 What number does this shop app show?
    let total = 590;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  40. 40.🔀 What number does this shop app show?
    let total = 200;
    if (total > 500) {
      total = total - 50;
    }
    show(total);

Answer key

  1. Gold
  2. Silver
  3. Low battery
  4. Welcome!
  5. 290
  6. Welcome!
  7. Welcome!
  8. Ask a parent
  9. Battery OK
  10. only one
  11. when the test is false
  12. ===
  13. 720
  14. PIN saved
  15. PIN saved
  16. 400
  17. 380
  18. Battery OK
  19. PIN saved
  20. pick one of two actions
  21. Battery OK
  22. Bronze
  23. 840
  24. 370
  25. Battery OK
  26. Use 4 digits
  27. Ask a parent
  28. Silver
  29. 330
  30. Use 4 digits
  31. Ask a parent
  32. 770
  33. Use 4 digits
  34. Ask a parent
  35. Use 4 digits
  36. Bronze
  37. Use 4 digits
  38. 820
  39. 540
  40. 200

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