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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 334 · 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 = "78474";
    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 = 11;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  3. 3.🔀 Which badge does this quiz app show?
    let marks = 39;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  4. 4.🔀 What number does this shop app show?
    let total = 620;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  5. 5.🔀 What does this battery rule show?
    let battery = 80;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  6. 6.🔀 When does the else part run? (a) never (b) when the test is false (c) always (d) when the test is true
  7. 7.🔀 What does if / else let an app do? (a) pick one of two actions (b) save a photo (c) draw a screen (d) repeat forever
  8. 8.🔀 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!
  9. 9.🔀 What number does this shop app show?
    let total = 240;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  10. 10.🔀 What does this sign-up rule show?
    let age = 16;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  11. 11.🔀 Which badge does this quiz app show?
    let marks = 66;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  12. 12.🔀 What number does this shop app show?
    let total = 840;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  13. 13.🔀 What does this sign-up rule show?
    let age = 8;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  14. 14.🔀 What number does this shop app show?
    let total = 690;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  15. 15.🔀 What does this PIN rule show?
    let pin = "41969";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  16. 16.🔀 What does this PIN rule show?
    let pin = "8220";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  17. 17.🔀 What does this battery rule show?
    let battery = 77;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  18. 18.🔀 With if / else if / else, how many parts run? (a) all of them (b) none (c) two (d) only one
  19. 19.🔀 What does this battery rule show?
    let battery = 43;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  20. 20.🔀 What number does this shop app show?
    let total = 320;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  21. 21.🔀 What does this PIN rule show?
    let pin = "1720";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  22. 22.🔀 What does this battery rule show?
    let battery = 29;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  23. 23.🔀 What does this PIN rule show?
    let pin = "40985";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  24. 24.🔀 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) Gold (b) Silver (c) Bronze
  25. 25.🔀 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!
  26. 26.🔀 Which badge does this quiz app show?
    let marks = 89;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  27. 27.🔀 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
  28. 28.🔀 What number does this shop app show?
    let total = 390;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  29. 29.🔀 What does this battery rule show?
    let battery = 27;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  30. 30.🔀 What does this PIN rule show?
    let pin = "989";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  31. 31.🔀 What does this PIN rule show?
    let pin = "625";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  32. 32.🔀 What does this PIN rule show?
    let pin = "7019";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  33. 33.🔀 What does this PIN rule show?
    let pin = "176";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  34. 34.🔀 In this course’s code, which sign tests “is equal to”? (a) = (b) !== (c) === (d) =>
  35. 35.🔀 What does this battery rule show?
    let battery = 12;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  36. 36.🔀 What does this battery rule show?
    let battery = 38;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  37. 37.🔀 What does this battery rule show?
    let battery = 81;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  38. 38.🔀 What number does this shop app show?
    let total = 610;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  39. 39.🔀 What number does this shop app show?
    let total = 670;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  40. 40.🔀 What does this PIN rule show?
    let pin = "152";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits

Answer key

  1. Use 4 digits
  2. Ask a parent
  3. Bronze
  4. 570
  5. Battery OK
  6. when the test is false
  7. pick one of two actions
  8. Ask a parent
  9. 240
  10. Welcome!
  11. Silver
  12. 790
  13. Ask a parent
  14. 640
  15. Use 4 digits
  16. PIN saved
  17. Battery OK
  18. only one
  19. Battery OK
  20. 320
  21. PIN saved
  22. Battery OK
  23. Use 4 digits
  24. Bronze
  25. Welcome!
  26. Gold
  27. Welcome!
  28. 390
  29. Battery OK
  30. Use 4 digits
  31. Use 4 digits
  32. PIN saved
  33. Use 4 digits
  34. ===
  35. Low battery
  36. Battery OK
  37. Battery OK
  38. 560
  39. 620
  40. Use 4 digits

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