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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 13 · 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) draw a screen (c) repeat forever (d) save a photo
  2. 2.🔀 What does this PIN rule show?
    let pin = "489";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  3. 3.🔀 What number does this shop app show?
    let total = 810;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  4. 4.🔀 When does the else part run? (a) always (b) never (c) when the test is false (d) when the test is true
  5. 5.🔀 What does this battery rule show?
    let battery = 58;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  6. 6.🔀 What number does this shop app show?
    let total = 540;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  7. 7.🔀 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!
  8. 8.🔀 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) Bronze (b) Silver (c) Gold
  9. 9.🔀 What number does this shop app show?
    let total = 200;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  10. 10.🔀 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) Bronze (b) Gold (c) Silver
  11. 11.🔀 Which badge does this quiz app show?
    let marks = 47;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  12. 12.🔀 What does this battery rule show?
    let battery = 16;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  13. 13.🔀 What does this battery rule show?
    let battery = 88;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  14. 14.🔀 Which badge does this quiz app show?
    let marks = 72;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  15. 15.🔀 What does this PIN rule show?
    let pin = "1419";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  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.🔀 What does this PIN rule show?
    let pin = "834";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  18. 18.🔀 What does this PIN rule show?
    let pin = "778";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  19. 19.🔀 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
  20. 20.🔀 What does this PIN rule show?
    let pin = "41973";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  21. 21.🔀 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
  22. 22.🔀 With if / else if / else, how many parts run? (a) none (b) two (c) only one (d) all of them
  23. 23.🔀 What does this PIN rule show?
    let pin = "33005";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  24. 24.🔀 What does this PIN rule show?
    let pin = "509";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  25. 25.🔀 What does this PIN rule show?
    let pin = "1271";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  26. 26.🔀 What does this battery rule show?
    let battery = 27;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  27. 27.🔀 What does this PIN rule show?
    let pin = "360";
    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 = 21;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  29. 29.🔀 What does this PIN rule show?
    let pin = "253";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  30. 30.🔀 Which badge does this quiz app show?
    let marks = 52;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  31. 31.🔀 What does this PIN rule show?
    let pin = "672";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  32. 32.🔀 What does this battery rule show?
    let battery = 42;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  33. 33.🔀 What does this PIN rule show?
    let pin = "296";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  34. 34.🔀 What does this PIN rule show?
    let pin = "17042";
    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 = 8;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  36. 36.🔀 Which badge does this quiz app show?
    let marks = 42;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  37. 37.🔀 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
  38. 38.🔀 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
  39. 39.🔀 What does this battery rule show?
    let battery = 20;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  40. 40.🔀 Which badge does this quiz app show?
    let marks = 91;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold

Answer key

  1. pick one of two actions
  2. Use 4 digits
  3. 760
  4. when the test is false
  5. Battery OK
  6. 490
  7. Ask a parent
  8. Gold
  9. 200
  10. Silver
  11. Bronze
  12. Low battery
  13. Battery OK
  14. Silver
  15. PIN saved
  16. Welcome!
  17. Use 4 digits
  18. Use 4 digits
  19. Ask a parent
  20. Use 4 digits
  21. Battery OK
  22. only one
  23. Use 4 digits
  24. Use 4 digits
  25. PIN saved
  26. Battery OK
  27. Use 4 digits
  28. Battery OK
  29. Use 4 digits
  30. Silver
  31. Use 4 digits
  32. Battery OK
  33. Use 4 digits
  34. Use 4 digits
  35. Ask a parent
  36. Bronze
  37. Ask a parent
  38. Battery OK
  39. Battery OK
  40. Gold

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