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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 428 · 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.🔀 What does this PIN rule show?
    let pin = "9454";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  2. 2.🔀 What does this sign-up rule show?
    let age = 13;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  3. 3.🔀 What does if / else let an app do? (a) repeat forever (b) pick one of two actions (c) draw a screen (d) save a photo
  4. 4.🔀 What does this battery rule show?
    let battery = 94;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  5. 5.🔀 What does this battery rule show?
    let battery = 58;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  6. 6.🔀 What does this PIN rule show?
    let pin = "397";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  7. 7.🔀 What does this PIN rule show?
    let pin = "806";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  8. 8.🔀 What does this PIN rule show?
    let pin = "36767";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  9. 9.🔀 Which badge does this quiz app show?
    let marks = 100;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  10. 10.🔀 What number does this shop app show?
    let total = 600;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  11. 11.🔀 What does this battery rule show?
    let battery = 54;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  12. 12.🔀 When does the else part run? (a) when the test is true (b) when the test is false (c) never (d) always
  13. 13.🔀 Which badge does this quiz app show?
    let marks = 93;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  14. 14.🔀 What number does this shop app show?
    let total = 250;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  15. 15.🔀 With if / else if / else, how many parts run? (a) none (b) two (c) all of them (d) only one
  16. 16.🔀 What does this sign-up rule show?
    let age = 9;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  17. 17.🔀 Which badge does this quiz app show?
    let marks = 98;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  18. 18.🔀 In this course’s code, which sign tests “is equal to”? (a) => (b) !== (c) === (d) =
  19. 19.🔀 What does this PIN rule show?
    let pin = "6885";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  20. 20.🔀 What does this battery rule show?
    let battery = 93;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  21. 21.🔀 What number does this shop app show?
    let total = 750;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  22. 22.🔀 What number does this shop app show?
    let total = 260;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  23. 23.🔀 What does >= mean? (a) less than (b) not equal (c) greater than or equal (d) smaller or equal
  24. 24.🔀 What does this sign-up rule show?
    let age = 16;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  25. 25.🔀 What does this battery rule show?
    let battery = 14;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  26. 26.🔀 What does this sign-up rule show?
    let age = 15;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  27. 27.🔀 What does this battery rule show?
    let battery = 46;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  28. 28.🔀 What number does this shop app show?
    let total = 680;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  29. 29.🔀 What number does this shop app show?
    let total = 420;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  30. 30.🔀 Which badge does this quiz app show?
    let marks = 99;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  31. 31.🔀 What number does this shop app show?
    let total = 540;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  32. 32.🔀 What does this sign-up rule show?
    let age = 10;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  33. 33.🔀 What does this PIN rule show?
    let pin = "618";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  34. 34.🔀 What does this PIN rule show?
    let pin = "440";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  35. 35.🔀 What does this battery rule show?
    let battery = 97;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  36. 36.🔀 What number does this shop app show?
    let total = 370;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  37. 37.🔀 What number does this shop app show?
    let total = 870;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  38. 38.🔀 What does this battery rule show?
    let battery = 2;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  39. 39.🔀 Which badge does this quiz app show?
    let marks = 58;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  40. 40.🔀 What number does this shop app show?
    let total = 860;
    if (total > 500) {
      total = total - 50;
    }
    show(total);

Answer key

  1. PIN saved
  2. Welcome!
  3. pick one of two actions
  4. Battery OK
  5. Battery OK
  6. Use 4 digits
  7. Use 4 digits
  8. Use 4 digits
  9. Gold
  10. 550
  11. Battery OK
  12. when the test is false
  13. Gold
  14. 250
  15. only one
  16. Ask a parent
  17. Gold
  18. ===
  19. PIN saved
  20. Battery OK
  21. 700
  22. 260
  23. greater than or equal
  24. Welcome!
  25. Low battery
  26. Welcome!
  27. Battery OK
  28. 630
  29. 420
  30. Gold
  31. 490
  32. Ask a parent
  33. Use 4 digits
  34. Use 4 digits
  35. Battery OK
  36. 370
  37. 820
  38. Low battery
  39. Silver
  40. 810

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