Final Exam Model Paper 3

An IndentationError. Python finds it before running anything.

help(): help(round) shows what round does and what it needs.

Turned, the photo no longer fills its rectangle, and empty triangles appear at the corners. The editor zooms in just enough to hide them, which cuts a thin strip off every edge.

temperature() measures the board’s processor chip, not the air. The chip warms itself while it works, so it reads a little warmer than the room.

1,080 : 1,350; dividing both by 270 gives 4 : 5, the tall shape for posts seen on an upright phone.

Line 2. 1000 > 1000 is False, so a bill of exactly Rs 1,000 misses out. “1,000 or more” is >=: if bill >= 1000:. (This is why the edge, 1,000 itself, is always worth testing.)

No. Translation tools make more mistakes in Nepali. English has one “you”, so the app must guess between तँ, तिमी, तपाईँ and हजुर, and a letter to the chairperson may come out rude. She should read it, and ask someone who knows both languages well to check it.

• i.A computer stores a float in binary, and many decimals, such as 1.1, can’t be written exactly in binary (as ⅓ can’t be written exactly in decimals). The tiny error shows when the answer is printed.
• ii.Round it to 2 decimal places:

tea = round(1.1 + 2.2, 2)print(tea, "kg")

3.3 kg

i. / always gives a float, so discount is 25.0, and pay is 250 − 25.0 = 225.0:

Pay Rs 225.0

ii. Turn the answer into a whole number, for example:

price = 250discount = price * 10 / 100pay = int(price - discount)print(f"Pay Rs {pay}")

Pay Rs 225

(discount = price * 10 // 100 also works here: // gives a whole number when both sides are ints.)

• i.The function prints each amount but doesn’t return it, so each call gives back None. Line 4 then tries None + None, and Python stops with a TypeError (unsupported operand type(s) for +: 'NoneType' and 'NoneType').
• ii.Change line 2 to return kg * rate:

def bill(kg, rate):    return kg * rate total = bill(2, 120) + bill(1, 80)print("Total:", total)

Total: 320

• i.No. A photo is protected for 25 years from when it was taken: 1995 + 25 = 2020, which has passed. (She should still credit the photographer, which is honest.)
• ii.Yes. Most work is protected for the maker’s whole life and 50 years after: 1990 + 50 = 2040. She needs permission to use it.

• i.The customer’s shadow stayed on the board for about 2 seconds, and the loop checked 10 times a second. Every check found the light below 40, so each check counted again: about 20 times.
• ii.It must count only the moment the light changes from bright to dark. It remembers whether it was dark the last time round the loop (a variable like was_dark), and counts only when it is dark now but wasn’t before.

Article 28 of the Constitution makes privacy a right. The Privacy Act, 2075 (2018) protects personal data. It requires, for example, a person’s consent before their personal data is collected; or that data collected with consent is used only for the purpose it was collected for; or that a parent or guardian agrees before an under-18’s private matters are shared.

Prompt B. It gives the context (Grade 8, a two-minute speech, Tamu Lhosar of the Gurung community), the format (5 points, one short sentence each) and a limit (which points to check), so the answer fits her job. Prompt A is vague, so it gets a long, general answer, perhaps about the wrong Lhosar (Nepal celebrates three: Tamu Lhosar of the Gurungs, Sonam Lhosar of the Tamangs and Gyalpo Lhosar of the Sherpas, among others). She still writes the speech herself and checks every point.

i.

beads = int(input("Stall keeper, the number of beads: "))guesses = 0guess = 0while guess != beads:    guess = int(input("Your guess: "))    guesses = guesses + 1    if guess < beads:        print("More")    elif guess > beads:        print("Fewer")print("Right! You took", guesses, "guesses.")if guesses <= 6:    print("You win a prize!")

With 37 beads, and the guesses 25, 40, 35, 37:

Stall keeper, the number of beads: 37Your guess: 25MoreYour guess: 40FewerYour guess: 35MoreYour guess: 37Right! You took 4 guesses.You win a prize!

ii. input() always gives a string. Comparing a string with a number with < is a TypeError; and if both stayed strings, < would compare them as text, letter by letter, so "9" < "37" would be False, and the hints would be wrong.

i. The sorted part is in bold.

• ii.1 + 1 + 3 + 4 = 9 comparisons and 1 + 0 + 2 + 3 = 6 swaps.
• iii.6 swaps: on the same list, the two sorts make the same swaps. Insertion sort usually makes fewer comparisons, because it stops as soon as an item is in place, while bubble sort compares every pair in every pass.

• i.<meta charset="utf-8">, in the <head> (usually its first line). It tells the browser to read the page’s bytes as UTF-8, the way Nepali text is stored.
• ii.So that a screen reader reads it with a Nepali voice instead of English rules, and browsers and search engines know the page is in Nepali.
• iii.padding is the space inside the border, between it and the text (10 px); border is a 2 px dark red line round the paragraph; margin is the space outside the border, between it and the elements around it (20 px).
• iv.Only the first paragraph, the date: .note selects elements with class="note", and the second paragraph has no class.

• i.Her email is the master key: “Forgot password?” on her other accounts sends a reset link or code to it, so whoever controls her email can take over almost all her accounts.
• ii.Attackers try a leaked password on other websites too. With the same password, the game’s leak opens her email and classroom.
• iii.One-time codes an account gives when two-step login is switched on, each good for one login, for when her phone is lost. She should write them on paper and keep them safe at home, never only on her phone.
• iv.Any one: it makes a different, strong password for every account (so one leak opens only one account); it warns when a password is reused or found in a breach; it fills in a password only on the real website.

visitors = 0money = 0answer = input("Age of the visitor (or done): ")while answer != "done":    age = int(answer)    visitors = visitors + 1    if age < 5:        print("Free entry")    elif age < 15:        print("Pay Rs 20")        money = money + 20    else:        print("Pay Rs 50")        money = money + 50    answer = input("Age of the visitor (or done): ")print("Visitors:", visitors)print("Money collected: Rs", money)

Age of the visitor (or done): 4Free entryAge of the visitor (or done): 12Pay Rs 20Age of the visitor (or done): 35Pay Rs 50Age of the visitor (or done): doneVisitors: 3Money collected: Rs 70

The answer is kept as text until the program knows it isn’t done; only then is it turned into a number. Other wordings of the messages are fine.

i. and ii. A ValueError, on line 2:

Traceback (most recent call last):  File "main.py", line 2, in <module>    kg = int(input("How many kg of apples? "))ValueError: invalid literal for int() with base 10: '2.5'

int() can turn only a whole number’s text into a number. "2.5" has a decimal point, so int() can’t convert it.

iii. Use float(), which takes decimals:

rate = 180kg = float(input("How many kg of apples? "))print("Pay Rs", rate * kg)

How many kg of apples? 2.5Pay Rs 450.0

iv.

One good page (yours will be different):

<!DOCTYPE html><html lang="en">  <head>    <meta charset="utf-8">    <meta name="viewport" content="width=device-width, initial-scale=1">    <title>Tamu Lhosar at Our School</title>    <link rel="stylesheet" href="style.css">  </head>  <body>    <h1>Tamu Lhosar at Our School</h1>    <p>Tamu Lhosar, on Poush 15, is the new year of the Gurung community. Our school celebrates it with a program in the yard.</p>    <h2>At the program</h2>    <ul>      <li>Ghatu and other Gurung dances</li>      <li>Songs by Grade 8 students</li>      <li>Snacks shared by families</li>    </ul>    <img src="lhosar.jpg" alt="A row of smiling Gurung women in bright Lhosar dress, with gold earrings and headbands, at Tamu Lhosar">  </body></html>

body {  font-family: sans-serif;} h1 {  color: #8b1a1a;} img {  max-width: 100%;}

The max-width: 100% rule keeps the photo inside a phone’s screen.

• i.The gatekeeper types either an age or the word done, so the answer must stay text until the program knows which it is. With int(input(…)), typing done would stop the program with a ValueError, because int() can’t turn the word into a number, so the totals would never be printed.
• ii.A ValueError is a value of the right type that can’t be used: int() takes a string, but not the string "2.5". A TypeError is a value of the wrong type for the operation, such as adding None to a number, or joining a number to a string with +.
• iii.A credit with what, who, where and which license, for example: “Photo: Gurung women at Tamu Lhosar, by Amarchobiabhi, CC BY-SA 4.0, via Wikimedia Commons.” The license allows the use only with that credit. For a photo of my own, I would need the women’s agreement before putting it online, because people who can be recognized should agree to be shown.