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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 635 · 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) pick one of two actions (b) repeat forever (c) save a photo (d) draw a screen
  2. 2.🔀 What does this battery rule show?
    let battery = 45;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  3. 3.🔀 What does this PIN rule show?
    let pin = "24488";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  4. 4.🔀 Which badge does this quiz app show?
    let marks = 49;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  5. 5.🔀 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
  6. 6.🔀 With if / else if / else, how many parts run? (a) all of them (b) none (c) two (d) only one
  7. 7.🔀 What does this PIN rule show?
    let pin = "261";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  8. 8.🔀 In this course’s code, which sign tests “is equal to”? (a) === (b) => (c) = (d) !==
  9. 9.🔀 What does this battery rule show?
    let battery = 30;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  10. 10.🔀 What does this sign-up rule show?
    let age = 11;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  11. 11.🔀 What number does this shop app show?
    let total = 550;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  12. 12.🔀 What number does this shop app show?
    let total = 620;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  13. 13.🔀 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) Gold (c) Silver
  14. 14.🔀 What does this sign-up rule show?
    let age = 8;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  15. 15.🔀 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
  16. 16.🔀 What number does this shop app show?
    let total = 420;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  17. 17.🔀 What does this battery rule show?
    let battery = 57;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  18. 18.🔀 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
  19. 19.🔀 What does this PIN rule show?
    let pin = "824";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  20. 20.🔀 What does >= mean? (a) greater than or equal (b) smaller or equal (c) less than (d) not equal
  21. 21.🔀 What number does this shop app show?
    let total = 670;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  22. 22.🔀 What does this battery rule show?
    let battery = 86;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  23. 23.🔀 When does the else part run? (a) always (b) never (c) when the test is true (d) when the test is false
  24. 24.🔀 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
  25. 25.🔀 What does this PIN rule show?
    let pin = "30684";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  26. 26.🔀 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!
  27. 27.🔀 Which badge does this quiz app show?
    let marks = 43;
    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 = 62;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  29. 29.🔀 What number does this shop app show?
    let total = 350;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  30. 30.🔀 What does this PIN rule show?
    let pin = "324";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  31. 31.🔀 What does this PIN rule show?
    let pin = "847";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  32. 32.🔀 What number does this shop app show?
    let total = 520;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  33. 33.🔀 What does this battery rule show?
    let battery = 6;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  34. 34.🔀 What does this PIN rule show?
    let pin = "106";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  35. 35.🔀 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
  36. 36.🔀 What does this PIN rule show?
    let pin = "2573";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  37. 37.🔀 Which badge does this quiz app show?
    let marks = 75;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  38. 38.🔀 What does this PIN rule show?
    let pin = "41359";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  39. 39.🔀 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
  40. 40.🔀 What number does this shop app show?
    let total = 770;
    if (total > 500) {
      total = total - 50;
    }
    show(total);

Answer key

  1. pick one of two actions
  2. Battery OK
  3. Use 4 digits
  4. Bronze
  5. Welcome!
  6. only one
  7. Use 4 digits
  8. ===
  9. Battery OK
  10. Ask a parent
  11. 500
  12. 570
  13. Silver
  14. Ask a parent
  15. Low battery
  16. 420
  17. Battery OK
  18. Ask a parent
  19. Use 4 digits
  20. greater than or equal
  21. 620
  22. Battery OK
  23. when the test is false
  24. Welcome!
  25. Use 4 digits
  26. Welcome!
  27. Bronze
  28. Battery OK
  29. 350
  30. Use 4 digits
  31. Use 4 digits
  32. 470
  33. Low battery
  34. Use 4 digits
  35. Ask a parent
  36. PIN saved
  37. Silver
  38. Use 4 digits
  39. Gold
  40. 720

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