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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 870 · 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.🔀 With if / else if / else, how many parts run? (a) all of them (b) none (c) two (d) only one
  2. 2.🔀 When does the else part run? (a) when the test is false (b) always (c) never (d) when the test is true
  3. 3.🔀 What does this PIN rule show?
    let pin = "446";
    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 = 84;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  5. 5.🔀 What number does this shop app show?
    let total = 530;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  6. 6.🔀 What does this sign-up rule show?
    let age = 16;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  7. 7.🔀 What does this PIN rule show?
    let pin = "12814";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  8. 8.🔀 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) Bronze (b) Gold (c) Silver
  9. 9.🔀 What does this battery rule show?
    let battery = 21;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  10. 10.🔀 What does this sign-up rule show?
    let age = 14;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  11. 11.🔀 What does this PIN rule show?
    let pin = "4020";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  12. 12.🔀 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
  13. 13.🔀 What number does this shop app show?
    let total = 230;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  14. 14.🔀 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!
  15. 15.🔀 What number does this shop app show?
    let total = 240;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  16. 16.🔀 What does this battery rule show?
    let battery = 72;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  17. 17.🔀 What number does this shop app show?
    let total = 490;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  18. 18.🔀 What does this battery rule show?
    let battery = 29;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  19. 19.🔀 What does this battery rule show?
    let battery = 35;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  20. 20.🔀 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!
  21. 21.🔀 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
  22. 22.🔀 What does >= mean? (a) greater than or equal (b) not equal (c) less than (d) smaller or equal
  23. 23.🔀 What does this PIN rule show?
    let pin = "324";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  24. 24.🔀 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
  25. 25.🔀 What does this battery rule show?
    let battery = 84;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  26. 26.🔀 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
  27. 27.🔀 What does this battery rule show?
    let battery = 34;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  28. 28.🔀 What number does this shop app show?
    let total = 550;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  29. 29.🔀 What number does this shop app show?
    let total = 670;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  30. 30.🔀 What does this PIN rule show?
    let pin = "7633";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  31. 31.🔀 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
  32. 32.🔀 What number does this shop app show?
    let total = 390;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  33. 33.🔀 What number does this shop app show?
    let total = 590;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  34. 34.🔀 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
  35. 35.🔀 What does if / else let an app do? (a) draw a screen (b) save a photo (c) pick one of two actions (d) repeat forever
  36. 36.🔀 In this course’s code, which sign tests “is equal to”? (a) = (b) => (c) === (d) !==
  37. 37.🔀 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
  38. 38.🔀 What does this battery rule show?
    let battery = 90;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  39. 39.🔀 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) Bronze (c) Gold
  40. 40.🔀 What does this battery rule show?
    let battery = 25;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK

Answer key

  1. only one
  2. when the test is false
  3. Use 4 digits
  4. Gold
  5. 480
  6. Welcome!
  7. Use 4 digits
  8. Bronze
  9. Battery OK
  10. Welcome!
  11. PIN saved
  12. Low battery
  13. 230
  14. Ask a parent
  15. 240
  16. Battery OK
  17. 490
  18. Battery OK
  19. Battery OK
  20. Ask a parent
  21. Low battery
  22. greater than or equal
  23. Use 4 digits
  24. Ask a parent
  25. Battery OK
  26. Welcome!
  27. Battery OK
  28. 500
  29. 620
  30. PIN saved
  31. Battery OK
  32. 390
  33. 540
  34. Welcome!
  35. pick one of two actions
  36. ===
  37. Ask a parent
  38. Battery OK
  39. Bronze
  40. Battery OK

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