Final Exam Model Paper 6

int(): int("25") gives the number 25.

An argument: the value given to the function when it is called. Inside the function, it goes into the matching parameter.

The voice that reaches the microphone gets stronger as the phone comes closer (at half the distance, twice as strong), while the room’s noise stays the same. So the voice is much louder than the noise.

Flashing copied the program into the board’s own storage. The board runs it from there by itself; the computer was only needed to write the program and copy it in.

2 GB = 2 × 1,024 = 2,048 MB, and 2,048 ÷ 100 ≈ 20 minutes.

Line 5 sets rainy to 1 again on each rainy day instead of adding 1 to it, so it never goes past 1. It should be rainy = rainy + 1.

The official forecast. A chatbot learned from text collected up to a certain date, so unless it searches as it answers, it knows nothing about tomorrow, and it may still write a confident, made-up answer. The forecast is made from today’s measurements by people who are responsible for it.

• i.Python does / before +, as in mathematics, so it worked out 20 / 2 first (10.0) and then added 12: 22.0.
• ii.Brackets make the addition happen first:

morning = 12afternoon = 20average = (morning + afternoon) / 2print("Average:", average)

Average: 16.0

i. tank -= 120 means tank = tank - 120, and += adds in the same way: 500 − 120 − 90 + 300 = 590.

Liters in the tank: 590

ii. The tank is full at 1,000 liters, so the room left is 1,000 minus what is in it:

tank = 500tank -= 120tank -= 90tank += 300print("Liters in the tank:", tank)print("Room for:", 1000 - tank)

Liters in the tank: 590Room for: 410

i.

Welcome to Rara National Park!Stay on the trail.Take your rubbish home.Enjoy the lake.

ii. Lines 1 to 3 only define the function: Python remembers what park_rules means and goes on to line 5, without running the body. The body runs only when the function is called, on line 6; then Python comes back to the line after the call, line 7.

def water_needed(people, days):    return people * days * 3 print(water_needed(4, 3) + water_needed(2, 3))

54

(water_needed(6, 3) gives the same 54.)

i. For example:

1. The shore with plastic on it, in the morning (5 seconds)
2. The class with gloves and sacks, setting out (6)
3. Close-ups of hands picking up bottles and wrappers (10)
4. A student explaining why plastic harms the lake (20)
5. The full sacks lined up (6)
6. The clean shore at the end (5)

Six shots, about 52 seconds, leave room for a title and credits.
ii. Any two: trim the start and end of every clip (the wobble as the button was pressed, the moment before anything happened); split long clips and delete their dull middles; delete whole shots that are dull or repeat another. If a clip is boring to the person who filmed it, it is more boring to everyone else.

• i.Input: the sensors measuring the water level in the river. Output: the sirens in four places downstream.
• ii.A flood takes time to travel 6 km down the river. Sensing it far upstream sets off the sirens before it arrives, giving people about 5 to 8 minutes to get away from the river.

• Given: what you typed or posted yourself, such as your date of birth when you signed up, or a photo.
• Recorded: what the app noted as you used it, such as the time you opened it, how long you watched each video, or where the phone was.
• Guessed (inferred): what a computer worked out from the other two without asking, such as “likes cricket” or “probably a student”.

The advice is risky. Chatbots sometimes make up the names of libraries that sound right but don’t exist, and a criminal can publish harmful code under such a name, waiting for someone to install it. Dawa should first check that the library is real, well known and trusted (or ask his teacher), and never install it just because an AI named it.

i.

hottest = int(input("Temperature on day 1: "))hottest_day = 1hot_days = 0if hottest > 35:    hot_days = 1for day in range(2, 8):    temp = int(input(f"Temperature on day {day}: "))    if temp > hottest:        hottest = temp        hottest_day = day    if temp > 35:        hot_days = hot_days + 1print("Hottest:", hottest, "on day", hottest_day)print("Days above 35:", hot_days)if hot_days >= 3:    print("Heat warning!")

For 33, 36, 38, 34, 37, 31, 35:

Temperature on day 1: 33Temperature on day 2: 36Temperature on day 3: 38Temperature on day 4: 34Temperature on day 5: 37Temperature on day 6: 31Temperature on day 7: 35Hottest: 38 on day 3Days above 35: 3Heat warning!

ii. Starting from 0 works only while some temperature is above 0. The same program used in Jumla in Poush, when every reading could be below 0, would print 0, a temperature that wasn’t in the list. Starting from the first value works for any temperatures. (A program that starts hottest at 0, and loops over all 7 days, is accepted in i for these readings.)

i. len(rain) is 5, so i goes 0 to 4. Positions 0 (42) and 2 (35) are above 30; the others (18, 9, 27) are not:

Mugu had heavy rainHumla had heavy rain2 of 5 districts

• ii.rain[3] is 9 (positions start at 0: 42, 18, 35, 9), and districts[0] is "Mugu", the first item.
• iii.It stops with an IndexError: a list of 5 items has the positions 0 to 4 only, so there is no position 5.

• i.As a table of two rows and two columns: a header row with “Fact” and “Rara Lake” (in bold, because they are <th> header cells), and under it a row with “Height above sea level” and “2,990 m”.
• ii..note picks every element with class="note": here the first paragraph. The rule makes its text pale gray (#aaaaaa) and 20 pixels high.
• iii.Any two:

• The note’s gray #aaaaaa on white has a contrast of only about 2.3 : 1, too faint to read in sunlight or on a cheap screen. Use a darker gray, such as #555555, or at least #767676 (4.5 : 1).
• The link says “click here”, which tells a screen-reader user who lists the links nothing. Make the link words say where it goes: <a href="trek.html">the trek to Rara Lake</a>.
• There is no viewport line, so a phone lays it out as a screen about 980 px wide and shrinks it. Add <meta name="viewport" content="width=device-width, initial-scale=1"> in the head.

• i.The phone’s Storage settings, which show what fills it, biggest first.
• ii.A cache is a store of spare copies an app keeps to work faster, such as pictures from a feed he scrolled through. It is safe to clear because the app can fetch them all again.
• iii.His settings, his login and what the app holds for him, such as chats not yet backed up: clearing an app’s data is like installing it again from scratch.
• iv.That the photos are backed up somewhere else, and that he has checked the backup, so they aren’t the only copies.

boat_holds = 6total_people = 0total_boats = 0people = int(input("How many people in this group? (0 to stop) "))while people != 0:    boats = people // boat_holds    if people % boat_holds > 0:        boats = boats + 1    print("Boats needed:", boats)    total_people = total_people + people    total_boats = total_boats + boats    people = int(input("How many people in this group? (0 to stop) "))print("People today:", total_people)print("Boats today:", total_boats)

How many people in this group? (0 to stop) 4Boats needed: 1How many people in this group? (0 to stop) 13Boats needed: 3How many people in this group? (0 to stop) 6Boats needed: 1How many people in this group? (0 to stop) 0People today: 23Boats today: 5

A while loop fits, because nobody knows in advance how many groups will come. Other ways of finding the boats are fine, such as adding a boat while people are left. Other wordings of the messages are fine.

i. and ii. A SyntaxError, on line 4:

  File "main.py", line 4    print("Rain recorded:" rain, "mm")          ^^^^^^^^^^^^^^^^^^^^^SyntaxError: invalid syntax. Perhaps you forgot a comma?

The things to print must be separated by commas. Between the string "Rain recorded:" and rain there is no comma, so Python can’t tell where one ends and the next begins.

iii. Put the comma in:

rain = int(input("Rain today, in mm: "))if rain > 50:    print("Heavy rain: keep away from the river.")print("Rain recorded:", rain, "mm")

Rain today, in mm: 18Rain recorded: 18 mm

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>Visit Rara Lake</title>    <link rel="stylesheet" href="style.css">  </head>  <body>    <h1>Visit Rara Lake</h1>    <p>Rara, in Mugu district, is Nepal’s biggest lake, ringed by pine forest at almost 3,000 meters.</p>    <h2>Take with you</h2>    <ul>      <li>A warm jacket for the cold mornings</li>      <li>A water bottle and purifying tablets</li>      <li>A bag to carry your rubbish back</li>    </ul>    <img src="rara.jpg" alt="Rara Lake at sunrise, with mist over the water, forested hills behind and a wooden viewing tower on the shore">  </body></html>

body {  font-family: sans-serif;  background-color: #eef6f8;} h1 {  color: #1d4e6b;} img {  max-width: 100%;}

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

• i.people // 6 gives the full boats, and people % 6 the people left over. If anyone is left over (% 6 more than 0), they need one more boat. For 12, 12 // 6 is 2 and 12 % 6 is 0: nobody is left over, so it prints 2 boats, with both full.
• ii.The comma separates the things to print: here a string and a number. Without it, Python sees two values side by side with nothing to say what to do with them. When it prints, print puts one space between the things, so Rain recorded: 18 mm comes out with a space after the colon and before mm, and the comma itself isn’t printed.
• iii.The browser uses the first font in the list that the device has: Noto Sans Devanagari if it is there, else Nirmala UI. sans-serif is a general kind of font, not one font: if the device has neither named font, the browser still uses some plain sans-serif font of its own, rather than any font it likes.