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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 576 · 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 sign-up rule show?
    let age = 9;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }     (a) Welcome! (b) Ask a parent
  2. 2.🔀 What does this sign-up rule show?
    let age = 15;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }     (a) Ask a parent (b) Welcome!
  3. 3.🔀 What does if / else let an app do? (a) draw a screen (b) pick one of two actions (c) repeat forever (d) save a photo
  4. 4.🔀 What does this PIN rule show?
    let pin = "5469";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  5. 5.🔀 What does this battery rule show?
    let battery = 52;
    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 = "86874";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  7. 7.🔀 What number does this shop app show?
    let total = 640;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  8. 8.🔀 When does the else part run? (a) when the test is true (b) never (c) when the test is false (d) always
  9. 9.🔀 What does this PIN rule show?
    let pin = "5546";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  10. 10.🔀 What does this PIN rule show?
    let pin = "5129";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  11. 11.🔀 With if / else if / else, how many parts run? (a) only one (b) two (c) all of them (d) none
  12. 12.🔀 What number does this shop app show?
    let total = 400;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  13. 13.🔀 What number does this shop app show?
    let total = 370;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  14. 14.🔀 What number does this shop app show?
    let total = 240;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  15. 15.🔀 What does this PIN rule show?
    let pin = "11284";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  16. 16.🔀 What number does this shop app show?
    let total = 600;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  17. 17.🔀 What number does this shop app show?
    let total = 630;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  18. 18.🔀 What does this battery rule show?
    let battery = 79;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  19. 19.🔀 What does this PIN rule show?
    let pin = "619";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  20. 20.🔀 What does >= mean? (a) greater than or equal (b) less than (c) not equal (d) smaller or equal
  21. 21.🔀 What does this PIN rule show?
    let pin = "85736";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  22. 22.🔀 What does this PIN rule show?
    let pin = "77171";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  23. 23.🔀 What number does this shop app show?
    let total = 550;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  24. 24.🔀 What does this battery rule show?
    let battery = 16;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  25. 25.🔀 Which badge does this quiz app show?
    let marks = 36;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Silver (b) Gold (c) Bronze
  26. 26.🔀 What does this battery rule show?
    let battery = 63;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  27. 27.🔀 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
  28. 28.🔀 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
  29. 29.🔀 What does this PIN rule show?
    let pin = "933";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  30. 30.🔀 What number does this shop app show?
    let total = 830;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  31. 31.🔀 In this course’s code, which sign tests “is equal to”? (a) === (b) !== (c) => (d) =
  32. 32.🔀 Which badge does this quiz app show?
    let marks = 90;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Silver (b) Bronze (c) Gold
  33. 33.🔀 What does this PIN rule show?
    let pin = "509";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  34. 34.🔀 What number does this shop app show?
    let total = 870;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  35. 35.🔀 What does this battery rule show?
    let battery = 37;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  36. 36.🔀 What number does this shop app show?
    let total = 580;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  37. 37.🔀 What does this PIN rule show?
    let pin = "5184";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  38. 38.🔀 What does this sign-up rule show?
    let age = 17;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }     (a) Ask a parent (b) Welcome!
  39. 39.🔀 Which badge does this quiz app show?
    let marks = 32;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Silver (b) Gold (c) Bronze
  40. 40.🔀 What does this PIN rule show?
    let pin = "54515";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits

Answer key

  1. Ask a parent
  2. Welcome!
  3. pick one of two actions
  4. PIN saved
  5. Battery OK
  6. Use 4 digits
  7. 590
  8. when the test is false
  9. PIN saved
  10. PIN saved
  11. only one
  12. 400
  13. 370
  14. 240
  15. Use 4 digits
  16. 550
  17. 580
  18. Battery OK
  19. Use 4 digits
  20. greater than or equal
  21. Use 4 digits
  22. Use 4 digits
  23. 500
  24. Low battery
  25. Bronze
  26. Battery OK
  27. Battery OK
  28. Welcome!
  29. Use 4 digits
  30. 780
  31. ===
  32. Gold
  33. Use 4 digits
  34. 820
  35. Battery OK
  36. 530
  37. PIN saved
  38. Welcome!
  39. Bronze
  40. Use 4 digits

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