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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 157 · 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 = "82897";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  2. 2.🔀 What does this PIN rule show?
    let pin = "4716";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  3. 3.🔀 Which badge does this quiz app show?
    let marks = 64;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  4. 4.🔀 What does this battery rule show?
    let battery = 22;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  5. 5.🔀 With if / else if / else, how many parts run? (a) none (b) all of them (c) two (d) only one
  6. 6.🔀 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!
  7. 7.🔀 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
  8. 8.🔀 When does the else part run? (a) when the test is true (b) never (c) always (d) when the test is false
  9. 9.🔀 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!
  10. 10.🔀 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
  11. 11.🔀 In this course’s code, which sign tests “is equal to”? (a) !== (b) = (c) === (d) =>
  12. 12.🔀 What number does this shop app show?
    let total = 880;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  13. 13.🔀 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
  14. 14.🔀 What does this battery rule show?
    let battery = 8;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  15. 15.🔀 Which badge does this quiz app show?
    let marks = 51;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  16. 16.🔀 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
  17. 17.🔀 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
  18. 18.🔀 What does this PIN rule show?
    let pin = "526";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  19. 19.🔀 What number does this shop app show?
    let total = 690;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  20. 20.🔀 Which badge does this quiz app show?
    let marks = 54;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  21. 21.🔀 What number does this shop app show?
    let total = 350;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  22. 22.🔀 What does this PIN rule show?
    let pin = "798";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  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 = 44;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  25. 25.🔀 What does >= mean? (a) less than (b) not equal (c) smaller or equal (d) greater than or equal
  26. 26.🔀 What number does this shop app show?
    let total = 630;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  27. 27.🔀 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) Gold (b) Bronze (c) Silver
  28. 28.🔀 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
  29. 29.🔀 What does this PIN rule show?
    let pin = "999";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  30. 30.🔀 What does this PIN rule show?
    let pin = "502";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  31. 31.🔀 What does this PIN rule show?
    let pin = "6837";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  32. 32.🔀 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
  33. 33.🔀 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
  34. 34.🔀 What does this PIN rule show?
    let pin = "64335";
    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 = "60948";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  36. 36.🔀 What does this battery rule show?
    let battery = 11;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  37. 37.🔀 Which badge does this quiz app show?
    let marks = 20;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  38. 38.🔀 What number does this shop app show?
    let total = 200;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  39. 39.🔀 Which badge does this quiz app show?
    let marks = 57;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  40. 40.🔀 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) Bronze (b) Silver (c) Gold

Answer key

  1. Use 4 digits
  2. PIN saved
  3. Silver
  4. Battery OK
  5. only one
  6. Ask a parent
  7. pick one of two actions
  8. when the test is false
  9. Welcome!
  10. Battery OK
  11. ===
  12. 830
  13. Battery OK
  14. Low battery
  15. Silver
  16. Welcome!
  17. Welcome!
  18. Use 4 digits
  19. 640
  20. Silver
  21. 350
  22. Use 4 digits
  23. Ask a parent
  24. Bronze
  25. greater than or equal
  26. 580
  27. Silver
  28. Low battery
  29. Use 4 digits
  30. Use 4 digits
  31. PIN saved
  32. Ask a parent
  33. Ask a parent
  34. Use 4 digits
  35. Use 4 digits
  36. Low battery
  37. Bronze
  38. 200
  39. Silver
  40. Silver

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