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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 128 · 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 = "57334";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  2. 2.🔀 Which badge does this quiz app show?
    let marks = 89;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  3. 3.🔀 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) Gold (b) Silver (c) Bronze
  4. 4.🔀 With if / else if / else, how many parts run? (a) none (b) only one (c) two (d) all of them
  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 battery rule show?
    let battery = 21;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  7. 7.🔀 What does if / else let an app do? (a) repeat forever (b) pick one of two actions (c) draw a screen (d) save a photo
  8. 8.🔀 What does this PIN rule show?
    let pin = "71604";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  9. 9.🔀 What does this PIN rule show?
    let pin = "266";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  10. 10.🔀 In this course’s code, which sign tests “is equal to”? (a) = (b) === (c) !== (d) =>
  11. 11.🔀 What does this PIN rule show?
    let pin = "827";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  12. 12.🔀 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
  13. 13.🔀 What number does this shop app show?
    let total = 210;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  14. 14.🔀 What does this battery rule show?
    let battery = 32;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  15. 15.🔀 What does this PIN rule show?
    let pin = "18765";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  16. 16.🔀 What does this battery rule show?
    let battery = 81;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  17. 17.🔀 What does this PIN rule show?
    let pin = "5143";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  18. 18.🔀 When does the else part run? (a) when the test is false (b) never (c) always (d) when the test is true
  19. 19.🔀 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!
  20. 20.🔀 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) Silver (b) Gold (c) Bronze
  21. 21.🔀 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
  22. 22.🔀 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!
  23. 23.🔀 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
  24. 24.🔀 What number does this shop app show?
    let total = 630;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  25. 25.🔀 What does this PIN rule show?
    let pin = "215";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  26. 26.🔀 What does >= mean? (a) greater than or equal (b) smaller or equal (c) less than (d) not equal
  27. 27.🔀 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) Bronze (b) Silver (c) Gold
  28. 28.🔀 What does this PIN rule show?
    let pin = "9896";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  29. 29.🔀 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
  30. 30.🔀 What number does this shop app show?
    let total = 650;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  31. 31.🔀 What does this PIN rule show?
    let pin = "7307";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  32. 32.🔀 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
  33. 33.🔀 What number does this shop app show?
    let total = 280;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  34. 34.🔀 What does this PIN rule show?
    let pin = "9898";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  35. 35.🔀 Which badge does this quiz app show?
    let marks = 97;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  36. 36.🔀 What number does this shop app show?
    let total = 410;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  37. 37.🔀 What does this PIN rule show?
    let pin = "19773";
    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 = "4596";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  39. 39.🔀 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!
  40. 40.🔀 What does this PIN rule show?
    let pin = "657";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved

Answer key

  1. Use 4 digits
  2. Gold
  3. Silver
  4. only one
  5. Welcome!
  6. Battery OK
  7. pick one of two actions
  8. Use 4 digits
  9. Use 4 digits
  10. ===
  11. Use 4 digits
  12. Ask a parent
  13. 210
  14. Battery OK
  15. Use 4 digits
  16. Battery OK
  17. PIN saved
  18. when the test is false
  19. Welcome!
  20. Silver
  21. Ask a parent
  22. Ask a parent
  23. Ask a parent
  24. 580
  25. Use 4 digits
  26. greater than or equal
  27. Bronze
  28. PIN saved
  29. Battery OK
  30. 600
  31. PIN saved
  32. Welcome!
  33. 280
  34. PIN saved
  35. Gold
  36. 410
  37. Use 4 digits
  38. PIN saved
  39. Welcome!
  40. Use 4 digits

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