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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 344 · 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 if / else let an app do? (a) save a photo (b) repeat forever (c) pick one of two actions (d) draw a screen
  2. 2.🔀 Which badge does this quiz app show?
    let marks = 30;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  3. 3.🔀 In this course’s code, which sign tests “is equal to”? (a) === (b) !== (c) = (d) =>
  4. 4.🔀 What does this PIN rule show?
    let pin = "31241";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  5. 5.🔀 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!
  6. 6.🔀 What does this sign-up rule show?
    let age = 11;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  7. 7.🔀 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
  8. 8.🔀 What does this battery rule show?
    let battery = 42;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  9. 9.🔀 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) Bronze (b) Silver (c) Gold
  10. 10.🔀 What does this PIN rule show?
    let pin = "123";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  11. 11.🔀 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!
  12. 12.🔀 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!
  13. 13.🔀 When does the else part run? (a) always (b) when the test is false (c) never (d) when the test is true
  14. 14.🔀 What number does this shop app show?
    let total = 330;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  15. 15.🔀 What does this battery rule show?
    let battery = 88;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  16. 16.🔀 What does this PIN rule show?
    let pin = "92309";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  17. 17.🔀 Which badge does this quiz app show?
    let marks = 79;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  18. 18.🔀 Which badge does this quiz app show?
    let marks = 68;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  19. 19.🔀 What number does this shop app show?
    let total = 640;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  20. 20.🔀 With if / else if / else, how many parts run? (a) two (b) none (c) all of them (d) only one
  21. 21.🔀 Which badge does this quiz app show?
    let marks = 67;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  22. 22.🔀 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
  23. 23.🔀 Which badge does this quiz app show?
    let marks = 24;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  24. 24.🔀 What number does this shop app show?
    let total = 580;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  25. 25.🔀 What does >= mean? (a) greater than or equal (b) smaller or equal (c) less than (d) not equal
  26. 26.🔀 What does this PIN rule show?
    let pin = "201";
    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 = 260;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  28. 28.🔀 What number does this shop app show?
    let total = 520;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  29. 29.🔀 What does this PIN rule show?
    let pin = "138";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  30. 30.🔀 What number does this shop app show?
    let total = 600;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  31. 31.🔀 What number does this shop app show?
    let total = 230;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  32. 32.🔀 What does this battery rule show?
    let battery = 18;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  33. 33.🔀 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
  34. 34.🔀 Which badge does this quiz app show?
    let marks = 76;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  35. 35.🔀 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!
  36. 36.🔀 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
  37. 37.🔀 What does this PIN rule show?
    let pin = "39828";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  38. 38.🔀 What number does this shop app show?
    let total = 340;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  39. 39.🔀 What number does this shop app show?
    let total = 660;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  40. 40.🔀 What does this PIN rule show?
    let pin = "2068";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits

Answer key

  1. pick one of two actions
  2. Bronze
  3. ===
  4. Use 4 digits
  5. Welcome!
  6. Ask a parent
  7. Welcome!
  8. Battery OK
  9. Silver
  10. Use 4 digits
  11. Welcome!
  12. Ask a parent
  13. when the test is false
  14. 330
  15. Battery OK
  16. Use 4 digits
  17. Silver
  18. Silver
  19. 590
  20. only one
  21. Silver
  22. Ask a parent
  23. Bronze
  24. 530
  25. greater than or equal
  26. Use 4 digits
  27. 260
  28. 470
  29. Use 4 digits
  30. 550
  31. 230
  32. Low battery
  33. Battery OK
  34. Silver
  35. Ask a parent
  36. Low battery
  37. Use 4 digits
  38. 340
  39. 610
  40. PIN saved

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