Correct answer: Round. The ROUND function rounds a number to a specified number of digits.
Background: The syntax is =ROUND(number, num_digits).
Did you know? ROUNDUP and ROUNDDOWN force rounding in one direction.
Memory trick: ROUND rounds; TRUNC chops.
Correct answer: 15. Multiply the top and bottom by 1000: 0.03 ÷ 0.002 = 30 ÷ 2 = 15.
Background: Making both numbers whole removes the decimals.
Did you know? Dividing decimals: move the decimal point the same number of places in both.
Memory trick: Move 3 places: 30 ÷ 2 = 15.
Correct answer: 30000. Paid amount = 120,000 × 25/100 = 30,000.
Background: To find x% of a number, multiply the number by x/100.
Did you know? 25% is the same as one-fourth.
Memory trick: 25% = ¼ → 120,000 ÷ 4.
Correct answer: −3. Total = 5 × 5 = 25. The known numbers add up to 28, so x = 25 − 28 = −3.
Background: Average = sum of numbers ÷ how many numbers.
Did you know? A missing number can be negative.
Memory trick: Missing = (average × count) − known sum.
Correct answer: 13/4. Squaring both sides gives 4x + 3 = 16, so 4x = 13 and x = 13/4.
Background: Squaring removes the square root.
Did you know? Check: 4 × 13/4 + 3 = 16 and √16 = 4.
Memory trick: Square both sides first.
Correct answer: 1, 3. Factorising gives (x − 1)(x − 3) = 0, so x = 1 or x = 3.
Background: The x-intercepts are the points where the graph crosses the x-axis (y = 0).
Did you know? For x² + bx + c, find two numbers with product c and sum b: here −1 and −3.
Memory trick: x-intercepts = roots.
Correct answer: 12. Substituting x = −3 gives 9 + 6 − (m + 3) = 0, so 15 − m − 3 = 0 and m = 12.
Background: A zero of a polynomial is a value of x that makes the polynomial equal to 0.
Did you know? Check: (−3)² − 2(−3) − 15 = 9 + 6 − 15 = 0.
Memory trick: Zero → plug in and solve.
Correct answer: 380–700 nm. Human eyes see wavelengths of about 380 nm (violet) to 700 nm (red).
Background: Visible light is a small part of the electromagnetic spectrum.
Did you know? The colours are remembered as VIBGYOR.
Memory trick: 380 to 700 nm.
Correct answer: Al-Razi. Al-Razi (Rhazes) wrote Kitab al-Hawi, a large medical encyclopedia.
Background: Al-Hawi gathered medical knowledge from Greek, Indian, and Arabic sources.
Did you know? Al-Razi also wrote an early work distinguishing smallpox from measles.
Memory trick: Al-Hawi = Al-Razi.
Correct answer: Satellite. A body that orbits a planet is called a satellite, either natural (like the Moon) or artificial.
Background: Artificial satellites are used for communication, weather, and navigation.
Did you know? The first artificial satellite was Sputnik 1 in 1957.
Memory trick: Orbits a planet = satellite.
Correct answer: To hide the IP address and provide security. A proxy server acts as an intermediary between users and the internet, hiding the user’s IP address and adding security.
Background: Proxy servers can also filter content and store (cache) pages.
Did you know? A VPN works in a similar way by hiding your address.
Memory trick: Proxy = middleman that hides your IP.
Correct answer: Transition. The “On Mouse Click” option is in the Transitions tab, under Advance Slide.
Background: In the same group you can also set a time delay to advance slides automatically.
Did you know? The Transitions tab controls effects between slides.
Memory trick: Mouse click = Transitions tab.
Correct answer: POP3. POP3 (Post Office Protocol version 3) is designed specifically to retrieve and download emails from a mail server to a local client device.
Background: IMAP accesses and synchronizes mail directly on the server, while SMTP is used for sending outgoing emails.
Did you know? POP3 downloads emails and usually deletes them from the server unless configured otherwise.
Memory trick: POP3 = Post Office Download.
Correct answer: Gullies. Rills deepen and join to form gullies, which are larger channels cut by running water.
Background: Fluvial processes are those caused by running water.
Did you know? Heavily gullied land is called badlands.
Memory trick: Rills → gullies → gorges.
Correct answer: Shale. Slate is formed when shale is changed by low-grade metamorphism.
Background: Slate splits easily into thin sheets.
Did you know? It is commonly used for roof tiles and blackboards.
Memory trick: Shale → Slate.
Correct answer: Einstein. Albert Einstein proposed the theory of relativity (special in 1905, general in 1915).
Background: The theory changed our understanding of space, time, and gravity.
Did you know? Einstein won the Nobel Prize in 1921 for the photoelectric effect, not relativity.
Memory trick: Relativity → Einstein → E = mc².
Correct answer: 1, 2 and 3. Blood pressure depends on how narrow the vessels are, how strongly the ventricle pumps, and how much blood returns to the heart.
Background: Narrow vessels raise blood pressure, and wider vessels lower it.
Did you know? Blood pressure is measured with a sphygmomanometer.
Memory trick: Vessels + pump + return = all three.
Correct answer: Displacement. Displacement is the shortest straight-line distance from the starting point to the final position, with a direction.
Background: Displacement is a vector, while distance is a scalar.
Did you know? If you return to the starting point, your displacement is zero.
Memory trick: Displacement = start to end, straight.
Correct answer: 120 torr. Normal systolic blood pressure is about 120 torr (mmHg).
Background: Systolic pressure is measured when the heart contracts.
Did you know? Normal blood pressure is written as 120/80.
Memory trick: 120 over 80.
Correct answer: Dielectric heating. Microwave ovens heat food primarily through dielectric (dipolar) heating, where polar water molecules rotate rapidly in response to an alternating high-frequency electromagnetic field (2.45 GHz).
Background: While older guidebooks loosely referenced resonance, dielectric heating is the standard scientific explanation.
Did you know? Percy Spencer discovered microwave cooking in 1945 when a chocolate bar melted in his pocket near an active radar magnetron.
Memory trick: Microwave heating = Dielectric (dipolar water rotation) heating.
Correct answer: Upper & Lower plains. The Indus plain is divided into the Upper Indus Plain (Punjab) and the Lower Indus Plain (Sindh).
Background: The two parts are separated roughly near Mithankot, where the Panjnad joins the Indus.
Did you know? The Lower Indus Plain ends in the Indus Delta.
Memory trick: Indus = Upper + Lower.
Correct answer: Karakoram. K2 lies in the Karakoram Range in Gilgit-Baltistan.
Background: K2 is 8,611 m high, the second-highest mountain in the world.
Did you know? It is nicknamed the “Savage Mountain”.
Memory trick: K2 = Karakoram.
Correct answer: Pakistan. Nanga Parbat is in Gilgit-Baltistan, Pakistan.
Background: It is 8,126 m high, the ninth-highest mountain in the world.
Did you know? It is nicknamed “Killer Mountain”.
Memory trick: Nanga Parbat = Pakistan (Diamer).
Correct answer: Groundwater: Making the Invisible Visible. The theme of World Water Day 2022 was “Groundwater: Making the Invisible Visible”.
Background: Groundwater is the water stored underground, which is out of sight but vital.
Did you know? World Water Day is observed every year on 22 March.
Memory trick: 2022 = Groundwater (invisible → visible).
Correct answer: Kazakhstan. Kassym-Jomart Tokayev has been the President of Kazakhstan since 2019.
Background: He succeeded Nursultan Nazarbayev.
Did you know? Kazakhstan’s capital is Astana.
Memory trick: Tokayev = Kazakhstan.