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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 149 · 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 = "274";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  2. 2.🔀 What does this battery rule show?
    let battery = 23;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  3. 3.🔀 What does this battery rule show?
    let battery = 86;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  4. 4.🔀 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) Bronze (b) Silver (c) Gold
  5. 5.🔀 What number does this shop app show?
    let total = 260;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  6. 6.🔀 What does if / else let an app do? (a) pick one of two actions (b) repeat forever (c) draw a screen (d) save a photo
  7. 7.🔀 What number does this shop app show?
    let total = 770;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  8. 8.🔀 What number does this shop app show?
    let total = 230;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  9. 9.🔀 What does >= mean? (a) less than (b) smaller or equal (c) greater than or equal (d) not equal
  10. 10.🔀 What number does this shop app show?
    let total = 840;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  11. 11.🔀 What does this battery rule show?
    let battery = 88;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  12. 12.🔀 What does this sign-up rule show?
    let age = 10;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }     (a) Ask a parent (b) Welcome!
  13. 13.🔀 What does this battery rule show?
    let battery = 7;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  14. 14.🔀 When does the else part run? (a) always (b) when the test is false (c) never (d) when the test is true
  15. 15.🔀 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
  16. 16.🔀 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!
  17. 17.🔀 Which badge does this quiz app show?
    let marks = 69;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Bronze (b) Silver (c) Gold
  18. 18.🔀 What number does this shop app show?
    let total = 520;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  19. 19.🔀 What number does this shop app show?
    let total = 660;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  20. 20.🔀 What does this battery rule show?
    let battery = 39;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  21. 21.🔀 What does this battery rule show?
    let battery = 65;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  22. 22.🔀 What does this battery rule show?
    let battery = 63;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  23. 23.🔀 What number does this shop app show?
    let total = 400;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  24. 24.🔀 What number does this shop app show?
    let total = 880;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  25. 25.🔀 With if / else if / else, how many parts run? (a) two (b) all of them (c) none (d) only one
  26. 26.🔀 What number does this shop app show?
    let total = 440;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  27. 27.🔀 What does this PIN rule show?
    let pin = "68083";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  28. 28.🔀 What does this battery rule show?
    let battery = 15;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  29. 29.🔀 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
  30. 30.🔀 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
  31. 31.🔀 In this course’s code, which sign tests “is equal to”? (a) === (b) = (c) => (d) !==
  32. 32.🔀 What does this PIN rule show?
    let pin = "1239";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  33. 33.🔀 Which badge does this quiz app show?
    let marks = 35;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Silver (b) Bronze (c) Gold
  34. 34.🔀 What does this PIN rule show?
    let pin = "484";
    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 = "70479";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  36. 36.🔀 What number does this shop app show?
    let total = 470;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  37. 37.🔀 What does this PIN rule show?
    let pin = "246";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  38. 38.🔀 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
  39. 39.🔀 Which badge does this quiz app show?
    let marks = 27;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Bronze (b) Gold (c) Silver
  40. 40.🔀 What number does this shop app show?
    let total = 280;
    if (total > 500) {
      total = total - 50;
    }
    show(total);

Answer key

  1. Use 4 digits
  2. Battery OK
  3. Battery OK
  4. Bronze
  5. 260
  6. pick one of two actions
  7. 720
  8. 230
  9. greater than or equal
  10. 790
  11. Battery OK
  12. Ask a parent
  13. Low battery
  14. when the test is false
  15. Bronze
  16. Welcome!
  17. Silver
  18. 470
  19. 610
  20. Battery OK
  21. Battery OK
  22. Battery OK
  23. 400
  24. 830
  25. only one
  26. 440
  27. Use 4 digits
  28. Low battery
  29. Welcome!
  30. Ask a parent
  31. ===
  32. PIN saved
  33. Bronze
  34. Use 4 digits
  35. Use 4 digits
  36. 470
  37. Use 4 digits
  38. Battery OK
  39. Bronze
  40. 280

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