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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 904 · 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 number does this shop app show?
    let total = 320;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  2. 2.🔀 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
  3. 3.🔀 What does this PIN rule show?
    let pin = "94606";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  4. 4.🔀 What does this battery rule show?
    let battery = 1;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  5. 5.🔀 What does this PIN rule show?
    let pin = "11933";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  6. 6.🔀 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) Silver (b) Gold (c) Bronze
  7. 7.🔀 What does this battery rule show?
    let battery = 67;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  8. 8.🔀 What does this battery rule show?
    let battery = 5;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  9. 9.🔀 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
  10. 10.🔀 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
  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.🔀 With if / else if / else, how many parts run? (a) two (b) only one (c) all of them (d) none
  13. 13.🔀 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
  14. 14.🔀 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
  15. 15.🔀 What number does this shop app show?
    let total = 640;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  16. 16.🔀 What does this PIN rule show?
    let pin = "173";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  17. 17.🔀 What does this battery rule show?
    let battery = 78;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  18. 18.🔀 What does this PIN rule show?
    let pin = "809";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  19. 19.🔀 What does this battery rule show?
    let battery = 3;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  20. 20.🔀 In this course’s code, which sign tests “is equal to”? (a) === (b) !== (c) = (d) =>
  21. 21.🔀 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!
  22. 22.🔀 What number does this shop app show?
    let total = 860;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  23. 23.🔀 Which badge does this quiz app show?
    let marks = 33;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Gold (b) Bronze (c) Silver
  24. 24.🔀 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) Silver (c) Gold
  25. 25.🔀 What number does this shop app show?
    let total = 680;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  26. 26.🔀 What does this battery rule show?
    let battery = 89;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  27. 27.🔀 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
  28. 28.🔀 What does >= mean? (a) smaller or equal (b) not equal (c) greater than or equal (d) less than
  29. 29.🔀 Which badge does this quiz app show?
    let marks = 38;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Silver (b) Gold (c) Bronze
  30. 30.🔀 What number does this shop app show?
    let total = 390;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  31. 31.🔀 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!
  32. 32.🔀 Which badge does this quiz app show?
    let marks = 81;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Gold (b) Silver (c) Bronze
  33. 33.🔀 What does this PIN rule show?
    let pin = "843";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  34. 34.🔀 What does this battery rule show?
    let battery = 12;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  35. 35.🔀 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
  36. 36.🔀 When does the else part run? (a) always (b) never (c) when the test is false (d) when the test is true
  37. 37.🔀 Which badge does this quiz app show?
    let marks = 32;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Bronze (b) Gold (c) Silver
  38. 38.🔀 What does this battery rule show?
    let battery = 99;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  39. 39.🔀 What does this PIN rule show?
    let pin = "924";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  40. 40.🔀 What does this PIN rule show?
    let pin = "93427";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved

Answer key

  1. 320
  2. Welcome!
  3. Use 4 digits
  4. Low battery
  5. Use 4 digits
  6. Silver
  7. Battery OK
  8. Low battery
  9. pick one of two actions
  10. Silver
  11. Silver
  12. only one
  13. Battery OK
  14. Ask a parent
  15. 590
  16. Use 4 digits
  17. Battery OK
  18. Use 4 digits
  19. Low battery
  20. ===
  21. Ask a parent
  22. 810
  23. Bronze
  24. Silver
  25. 630
  26. Battery OK
  27. Welcome!
  28. greater than or equal
  29. Bronze
  30. 390
  31. Ask a parent
  32. Gold
  33. Use 4 digits
  34. Low battery
  35. Ask a parent
  36. when the test is false
  37. Bronze
  38. Battery OK
  39. Use 4 digits
  40. Use 4 digits

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