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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 579 · 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.🔀 In this course’s code, which sign tests “is equal to”? (a) => (b) = (c) !== (d) ===
  2. 2.🔀 What number does this shop app show?
    let total = 360;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  3. 3.🔀 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
  4. 4.🔀 When does the else part run? (a) when the test is true (b) always (c) never (d) when the test is false
  5. 5.🔀 What does this PIN rule show?
    let pin = "541";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  6. 6.🔀 Which badge does this quiz app show?
    let marks = 55;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  7. 7.🔀 What number does this shop app show?
    let total = 460;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  8. 8.🔀 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) Gold (b) Silver (c) Bronze
  9. 9.🔀 What does this battery rule show?
    let battery = 71;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  10. 10.🔀 Which badge does this quiz app show?
    let marks = 40;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  11. 11.🔀 What does this battery rule show?
    let battery = 4;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  12. 12.🔀 Which badge does this quiz app show?
    let marks = 84;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  13. 13.🔀 Which badge does this quiz app show?
    let marks = 22;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  14. 14.🔀 Which badge does this quiz app show?
    let marks = 61;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  15. 15.🔀 What does this battery rule show?
    let battery = 15;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  16. 16.🔀 What does if / else let an app do? (a) save a photo (b) draw a screen (c) repeat forever (d) pick one of two actions
  17. 17.🔀 What does >= mean? (a) not equal (b) greater than or equal (c) smaller or equal (d) less than
  18. 18.🔀 What does this battery rule show?
    let battery = 65;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  19. 19.🔀 What number does this shop app show?
    let total = 630;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  20. 20.🔀 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
  21. 21.🔀 What does this PIN rule show?
    let pin = "66077";
    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 = 94;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  23. 23.🔀 Which badge does this quiz app show?
    let marks = 74;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  24. 24.🔀 What does this battery rule show?
    let battery = 16;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  25. 25.🔀 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!
  26. 26.🔀 What does this PIN rule show?
    let pin = "845";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  27. 27.🔀 What number does this shop app show?
    let total = 730;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  28. 28.🔀 With if / else if / else, how many parts run? (a) all of them (b) none (c) only one (d) two
  29. 29.🔀 What does this sign-up rule show?
    let age = 12;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  30. 30.🔀 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!
  31. 31.🔀 What does this PIN rule show?
    let pin = "6117";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  32. 32.🔀 What does this PIN rule show?
    let pin = "86932";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  33. 33.🔀 What does this battery rule show?
    let battery = 34;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  34. 34.🔀 What does this PIN rule show?
    let pin = "636";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  35. 35.🔀 What does this PIN rule show?
    let pin = "269";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  36. 36.🔀 What number does this shop app show?
    let total = 380;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  37. 37.🔀 What does this PIN rule show?
    let pin = "663";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  38. 38.🔀 What does this PIN rule show?
    let pin = "1046";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  39. 39.🔀 What number does this shop app show?
    let total = 240;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  40. 40.🔀 What does this PIN rule show?
    let pin = "8455";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits

Answer key

  1. ===
  2. 360
  3. Welcome!
  4. when the test is false
  5. Use 4 digits
  6. Silver
  7. 460
  8. Gold
  9. Battery OK
  10. Bronze
  11. Low battery
  12. Gold
  13. Bronze
  14. Silver
  15. Low battery
  16. pick one of two actions
  17. greater than or equal
  18. Battery OK
  19. 580
  20. Low battery
  21. Use 4 digits
  22. Battery OK
  23. Silver
  24. Low battery
  25. Ask a parent
  26. Use 4 digits
  27. 680
  28. only one
  29. Ask a parent
  30. Ask a parent
  31. PIN saved
  32. Use 4 digits
  33. Battery OK
  34. Use 4 digits
  35. Use 4 digits
  36. 380
  37. Use 4 digits
  38. PIN saved
  39. 240
  40. PIN saved

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