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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 71 · 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 = 90;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  2. 2.🔀 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
  3. 3.🔀 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!
  4. 4.🔀 What does this PIN rule show?
    let pin = "54069";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  5. 5.🔀 What number does this shop app show?
    let total = 350;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  6. 6.🔀 What does this battery rule show?
    let battery = 42;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  7. 7.🔀 What does this PIN rule show?
    let pin = "7313";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  8. 8.🔀 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
  9. 9.🔀 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!
  10. 10.🔀 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
  11. 11.🔀 What does this battery rule show?
    let battery = 6;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  12. 12.🔀 Which badge does this quiz app show?
    let marks = 72;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  13. 13.🔀 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
  14. 14.🔀 What does this battery rule show?
    let battery = 70;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  15. 15.🔀 With if / else if / else, how many parts run? (a) two (b) only one (c) none (d) all of them
  16. 16.🔀 What number does this shop app show?
    let total = 640;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  17. 17.🔀 What number does this shop app show?
    let total = 600;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  18. 18.🔀 What does this battery rule show?
    let battery = 90;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  19. 19.🔀 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
  20. 20.🔀 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
  21. 21.🔀 What does >= mean? (a) greater than or equal (b) not equal (c) smaller or equal (d) less than
  22. 22.🔀 What does this PIN rule show?
    let pin = "56266";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  23. 23.🔀 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!
  24. 24.🔀 Which badge does this quiz app show?
    let marks = 70;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  25. 25.🔀 Which badge does this quiz app show?
    let marks = 80;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  26. 26.🔀 What does this PIN rule show?
    let pin = "77474";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  27. 27.🔀 What does this battery rule show?
    let battery = 44;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  28. 28.🔀 What does this PIN rule show?
    let pin = "96499";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  29. 29.🔀 What number does this shop app show?
    let total = 380;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  30. 30.🔀 What does this battery rule show?
    let battery = 19;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  31. 31.🔀 What does this battery rule show?
    let battery = 77;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  32. 32.🔀 What does this PIN rule show?
    let pin = "41882";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  33. 33.🔀 In this course’s code, which sign tests “is equal to”? (a) !== (b) = (c) => (d) ===
  34. 34.🔀 What does this PIN rule show?
    let pin = "804";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  35. 35.🔀 What does this PIN rule show?
    let pin = "64345";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  36. 36.🔀 What number does this shop app show?
    let total = 710;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  37. 37.🔀 When does the else part run? (a) when the test is true (b) always (c) never (d) when the test is false
  38. 38.🔀 What number does this shop app show?
    let total = 620;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  39. 39.🔀 What number does this shop app show?
    let total = 210;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  40. 40.🔀 What does this battery rule show?
    let battery = 64;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery

Answer key

  1. Gold
  2. Bronze
  3. Welcome!
  4. Use 4 digits
  5. 350
  6. Battery OK
  7. PIN saved
  8. Battery OK
  9. Welcome!
  10. pick one of two actions
  11. Low battery
  12. Silver
  13. Ask a parent
  14. Battery OK
  15. only one
  16. 590
  17. 550
  18. Battery OK
  19. Battery OK
  20. Welcome!
  21. greater than or equal
  22. Use 4 digits
  23. Ask a parent
  24. Silver
  25. Gold
  26. Use 4 digits
  27. Battery OK
  28. Use 4 digits
  29. 380
  30. Low battery
  31. Battery OK
  32. Use 4 digits
  33. ===
  34. Use 4 digits
  35. Use 4 digits
  36. 660
  37. when the test is false
  38. 570
  39. 210
  40. Battery OK

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