BCS Preliminary Test cheat sheet

Bangla alphabet: 11 vowels (স্বরবর্ণ), 39 consonants (ব্যঞ্জনবর্ণ), 3 semivowels, 10 conjunct forms; মাত্রা count distinguishes full-form vowels from kar signs.

সন্ধি splits into স্বরসন্ধি (vowel+vowel), ব্যঞ্জনসন্ধি, and বিসর্গসন্ধি; e.g., বিদ্যা + আলয় = বিদ্যালয় (স্বরসন্ধি).

সমাস types: দ্বন্দ্ব, কর্মধারয়, তৎপুরুষ, বহুব্রীহি, দ্বিগু, অব্যয়ীভাব; বহুব্রীহি denotes another object, দ্বিগু denotes a quantity.

কারক-বিভক্তি: কর্তৃ (subject), কর্ম (object), করণ (instrument), সম্প্রদান (recipient), অপাদান (source), অধিকরণ (location).

Bengali literary periods: প্রাচীন (চর্যাপদ, ~950–1200 CE), মধ্যযুগ (শ্রীকৃষ্ণকীর্তন, মঙ্গলকাব্য), আধুনিক (post-1800).

চর্যাপদ is the earliest known Bangla text, discovered by হরপ্রসাদ শাস্ত্রী in 1907 in Nepal; composed by সিদ্ধাচার্যদের.

মাইকেল মধুসূদন দত্ত introduced অমিত্রাক্ষর ছন্দ in Bangla through মেঘনাদবধ কাব্য (1861).

রবীন্দ্রনাথ ঠাকুর won the Nobel Prize in Literature in 1913 for গীতাঞ্জলি (English: Song Offerings).

বাংলা একাডেমি was established in 1955 to promote Bangla language and literature; its headquarters is in Dhaka.

Parts of speech: noun, pronoun, verb, adjective, adverb, preposition, conjunction, interjection; articles (a/an/the) are determiners, not a separate part.

Twelve tenses derive from three times (past, present, future) × four aspects (simple, continuous, perfect, perfect continuous).

Active to passive: object becomes subject, verb becomes be + past participle, agent expressed with 'by'.

Conditional types: zero (general truth), first (real future), second (unreal present), third (unreal past); third uses had + past participle then would have + past participle.

Direct to indirect speech shifts tense one step back, changes pronouns by person rule (first-person follows speaker, second follows listener, third unchanged).

Literary periods: Old English (Beowulf), Middle English (Chaucer), Renaissance (Shakespeare, Spenser), Romantic (Wordsworth, Coleridge), Victorian (Tennyson, Dickens).

Shakespeare wrote 37 plays, 154 sonnets, and two narrative poems (Venus and Adonis, The Rape of Lucrece).

Figures of speech: simile (like/as), metaphor (direct comparison), personification, hyperbole, oxymoron, synecdoche, metonymy.

Phrasal verbs change meaning with the particle: 'give up' = surrender, 'give in' = yield, 'give away' = donate.

Percentage change = (new − old) / old × 100; successive changes multiply: (1+a)(1+b) − 1.

Simple interest = P × r × t; compound interest = P[(1+r)^t − 1]; for two years, CI − SI = P(r/100)².

Profit/loss percentage is calculated on cost price unless stated otherwise; selling price = CP × (100 ± percentage)/100.

Speed = distance / time; average speed for equal distances = 2ab/(a+b) (harmonic mean).

Work: if A alone takes x days and B alone y days, together = xy/(x+y) days.

Sum of first n natural numbers = n(n+1)/2; sum of squares = n(n+1)(2n+1)/6.

Area formulas: circle = πr², triangle = ½ × base × height, trapezium = ½(a+b)h, sphere surface = 4πr².

Pythagorean triplets (3,4,5), (5,12,13), (8,15,17), (7,24,25) speed mental calculation of right triangles.

Permutation nPr = n!/(n−r)!; combination nCr = n!/[r!(n−r)!]; nCr = nC(n−r).

Bangladesh independence declared 26 March 1971; Victory Day 16 December 1971; Language Movement martyrs commemorated 21 February 1952.

Bangladesh Constitution adopted 4 November 1972, effective 16 December 1972; original had 153 articles, 11 parts, preamble.

National symbols: national flower water lily (shapla), national fruit jackfruit, national bird oriental magpie-robin (doyel), national fish hilsa.

Administrative divisions number eight: Dhaka, Chattogram, Rajshahi, Khulna, Barishal, Sylhet, Rangpur, Mymensingh.

Sundarbans is the world's largest mangrove forest, a UNESCO World Heritage Site (1997), home of the Royal Bengal Tiger.

Cox's Bazar hosts the world's longest natural sandy sea beach (~120 km); Saint Martin's is Bangladesh's only coral island.

Bangladesh is a riverine delta formed by the Ganges–Brahmaputra–Meghna; largest river by width is the Meghna.

Bangladesh joined the United Nations in 1974; SAARC founded in Dhaka in 1985; headquarters of BIMSTEC is in Dhaka.

Padma Bridge opened 25 June 2022, connecting southwestern districts to the capital.

United Nations founded 24 October 1945; headquarters in New York; 193 member states; Security Council has 5 permanent members with veto.

Specialized UN agencies: WHO (Geneva), UNESCO (Paris), FAO (Rome), ILO (Geneva), UNICEF (New York), IMF and World Bank (Washington, DC).

SAARC founded 1985 in Dhaka, 8 members; ASEAN founded 1967 in Bangkok, 10 members; OIC founded 1969 in Rabat, 57 members.

European Union established by Maastricht Treaty (1993); euro currency introduced 1999; Nobel Peace Prize 2012.

G7 comprises USA, UK, France, Germany, Japan, Italy, Canada; G20 includes major economies and the EU.

Bretton Woods Conference (1944) created the IMF and the World Bank; both began operations in 1945–46.

Non-Aligned Movement founded at Belgrade (1961) after the Bandung Conference (1955).

Cold War ended with the dissolution of the Soviet Union in December 1991.

SI base units: metre (length), kilogram (mass), second (time), ampere (current), kelvin (temperature), mole (amount), candela (luminous intensity).

Newton's laws: inertia (F=0 → constant velocity), F = ma, action–reaction pairs equal and opposite.

Photosynthesis: 6CO₂ + 6H₂O + light → C₆H₁₂O₆ + 6O₂, occurring in chloroplasts using chlorophyll.

Human blood groups ABO and Rh; universal donor O−, universal recipient AB+; heart has four chambers.

DNA double helix described by Watson and Crick (1953); base pairing A–T, G–C.

Periodic table groups: alkali metals (Group 1), halogens (Group 17), noble gases (Group 18).

Speed of light in vacuum ≈ 3 × 10⁸ m/s; acceleration due to gravity g ≈ 9.8 m/s².

Vaccines work by stimulating antibody production; antibiotics target bacteria, not viruses.

Greenhouse gases include CO₂, CH₄, N₂O, water vapour, and CFCs; CO₂ is the largest anthropogenic contributor.

Computer generations: 1st vacuum tubes, 2nd transistors, 3rd integrated circuits, 4th microprocessors, 5th AI.

Binary to decimal: multiply each bit by 2^position from right; 1011₂ = 11₁₀.

Memory hierarchy: registers > cache > RAM > secondary storage, by speed and cost.

OSI model has 7 layers: Physical, Data Link, Network, Transport, Session, Presentation, Application; TCP/IP has 4.

IPv4 uses 32-bit addresses; IPv6 uses 128-bit addresses.

HTTP (port 80), HTTPS (443), FTP (21), SMTP (25), DNS (53), SSH (22).

1 byte = 8 bits; 1 KB = 1024 bytes; 1 MB = 1024 KB; 1 GB = 1024 MB.

SQL is a declarative query language; primary key uniquely identifies rows; foreign key references another table's primary key.

Malware categories: virus (needs host), worm (self-replicating), trojan (disguised), ransomware (encrypts and demands payment).

Core values: honesty, integrity, accountability, transparency, fairness, respect for rule of law.

Good governance characteristics (UNDP): participation, rule of law, transparency, responsiveness, consensus orientation, equity, effectiveness, accountability.

Corruption types include bribery, embezzlement, nepotism, extortion, and conflict of interest.

Transparency International publishes the Corruption Perceptions Index (CPI) ranking countries by perceived public-sector corruption.

Conflict of interest arises when private interest interferes with public duty; recusal is the standard remedy.

Whistleblowing is disclosure of wrongdoing; protections vary by jurisdiction and organization.

Code of conduct typically covers gifts, confidentiality, use of public resources, and political neutrality.

Bangladesh's Anti-Corruption Commission (ACC) was established in 2004 under the Anti-Corruption Commission Act.

Earth's layers: crust (continental ~35 km, oceanic ~7 km), mantle, outer core (liquid), inner core (solid iron-nickel).

Latitude lines run east–west; longitude lines run north–south; 1° latitude ≈ 111 km.

Tropic of Cancer (23.5°N) and Tropic of Capricorn (23.5°S) mark the tropics; equator is 0°.

Bangladesh lies between 20°34′N–26°38′N and 88°01′E–92°41′E; area ≈ 147,570 km².

Rivers of Bangladesh: Padma, Meghna, Jamuna, Brahmaputra, Karnaphuli (only major river rising within Bangladesh).

Climate of Bangladesh: tropical monsoon; seasons summer (Mar–May), monsoon (Jun–Sep), autumn, winter (Dec–Feb).

Highest peak globally: Mount Everest (8,849 m); Bangladesh's highest point is Keokradong (~1,230 m).

Largest ocean is the Pacific; deepest trench is the Mariana Trench (~11,000 m).

Soil types: alluvial (most of Bangladesh), red soil (Chittagong Hill Tracts), peat, coastal saline.

Greenhouse effect: trapped infrared radiation by atmospheric gases warms Earth; enhanced by anthropogenic emissions.

Ozone layer in the stratosphere absorbs UV-B; depleted by CFCs and halons; Montreal Protocol (1987) phases them out.

Kyoto Protocol (1997) set binding targets for developed countries; Paris Agreement (2015) targets ≤2°C warming, ideally 1.5°C.

Disaster cycle: mitigation, preparedness, response, recovery; Bangladesh uses a cyclone early-warning system and cyclone shelters.

Bangladesh is highly vulnerable to cyclones, floods, riverbank erosion, and salinity intrusion due to low elevation and dense population.

Biodiversity hotspots: Sundarbans (mangrove), Chittagong Hill Tracts; Ramsar sites include Tanguar Haor.

EIA (Environmental Impact Assessment) evaluates project impacts before approval; SEA applies at policy level.

Reduce, reuse, recycle (3R) hierarchy; waste segregation at source improves recycling efficiency.

Sendai Framework (2015–2030) sets global disaster risk reduction priorities: understanding risk, governance, investment, preparedness.

Greenhouse effect: trapped infrared radiation by atmospheric gases warms Earth; enhanced by anthropogenic emissions.

Ozone layer in the stratosphere absorbs UV-B; depleted by CFCs and halons; Montreal Protocol (1987) phases them out.

Kyoto Protocol (1997) set binding targets for developed countries; Paris Agreement (2015) targets ≤2°C warming, ideally 1.5°C.

Disaster cycle: mitigation, preparedness, response, recovery; Bangladesh uses a cyclone early-warning system and cyclone shelters.

Bangladesh is highly vulnerable to cyclones, floods, riverbank erosion, and salinity intrusion due to low elevation and dense population.

Biodiversity hotspots: Sundarbans (mangrove), Chittagong Hill Tracts; Ramsar sites include Tanguar Haor.

EIA (Environmental Impact Assessment) evaluates project impacts before approval; SEA applies at policy level.

Reduce, reuse, recycle (3R) hierarchy; waste segregation at source improves recycling efficiency.

Sendai Framework (2015–2030) sets global disaster risk reduction priorities: understanding risk, governance, investment, preparedness.

Bangla alphabet: 11 vowels (স্বরবর্ণ), 39 consonants (ব্যঞ্জনবর্ণ), 3 semivowels, 10 conjunct forms; মাত্রা count distinguishes full-form vowels from kar signs.

সন্ধি splits into স্বরসন্ধি (vowel+vowel), ব্যঞ্জনসন্ধি, and বিসর্গসন্ধি; e.g., বিদ্যা + আলয় = বিদ্যালয় (স্বরসন্ধি).

সমাস types: দ্বন্দ্ব, কর্মধারয়, তৎপুরুষ, বহুব্রীহি, দ্বিগু, অব্যয়ীভাব; বহুব্রীহি denotes another object, দ্বিগু denotes a quantity.

কারক-বিভক্তি: কর্তৃ (subject), কর্ম (object), করণ (instrument), সম্প্রদান (recipient), অপাদান (source), অধিকরণ (location).

Bengali literary periods: প্রাচীন (চর্যাপদ, ~950–1200 CE), মধ্যযুগ (শ্রীকৃষ্ণকীর্তন, মঙ্গলকাব্য), আধুনিক (post-1800).

চর্যাপদ is the earliest known Bangla text, discovered by হরপ্রসাদ শাস্ত্রী in 1907 in Nepal; composed by সিদ্ধাচার্যদের.

মাইকেল মধুসূদন দত্ত introduced অমিত্রাক্ষর ছন্দ in Bangla through মেঘনাদবধ কাব্য (1861).

রবীন্দ্রনাথ ঠাকুর won the Nobel Prize in Literature in 1913 for গীতাঞ্জলি (English: Song Offerings).

বাংলা একাডেমি was established in 1955 to promote Bangla language and literature; its headquarters is in Dhaka.

Parts of speech: noun, pronoun, verb, adjective, adverb, preposition, conjunction, interjection; articles (a/an/the) are determiners, not a separate part.

Twelve tenses derive from three times (past, present, future) × four aspects (simple, continuous, perfect, perfect continuous).

Active to passive: object becomes subject, verb becomes be + past participle, agent expressed with 'by'.

Conditional types: zero (general truth), first (real future), second (unreal present), third (unreal past); third uses had + past participle then would have + past participle.

Direct to indirect speech shifts tense one step back, changes pronouns by person rule (first-person follows speaker, second follows listener, third unchanged).

Literary periods: Old English (Beowulf), Middle English (Chaucer), Renaissance (Shakespeare, Spenser), Romantic (Wordsworth, Coleridge), Victorian (Tennyson, Dickens).

Shakespeare wrote 37 plays, 154 sonnets, and two narrative poems (Venus and Adonis, The Rape of Lucrece).

Figures of speech: simile (like/as), metaphor (direct comparison), personification, hyperbole, oxymoron, synecdoche, metonymy.

Phrasal verbs change meaning with the particle: 'give up' = surrender, 'give in' = yield, 'give away' = donate.

Percentage change = (new − old) / old × 100; successive changes multiply: (1+a)(1+b) − 1.

Simple interest = P × r × t; compound interest = P[(1+r)^t − 1]; for two years, CI − SI = P(r/100)².

Profit/loss percentage is calculated on cost price unless stated otherwise; selling price = CP × (100 ± percentage)/100.

Speed = distance / time; average speed for equal distances = 2ab/(a+b) (harmonic mean).

Work: if A alone takes x days and B alone y days, together = xy/(x+y) days.

Sum of first n natural numbers = n(n+1)/2; sum of squares = n(n+1)(2n+1)/6.

Area formulas: circle = πr², triangle = ½ × base × height, trapezium = ½(a+b)h, sphere surface = 4πr².

Pythagorean triplets (3,4,5), (5,12,13), (8,15,17), (7,24,25) speed mental calculation of right triangles.

Permutation nPr = n!/(n−r)!; combination nCr = n!/[r!(n−r)!]; nCr = nC(n−r).

Bangladesh independence declared 26 March 1971; Victory Day 16 December 1971; Language Movement martyrs commemorated 21 February 1952.

Bangladesh Constitution adopted 4 November 1972, effective 16 December 1972; original had 153 articles, 11 parts, preamble.

National symbols: national flower water lily (shapla), national fruit jackfruit, national bird oriental magpie-robin (doyel), national fish hilsa.

Administrative divisions number eight: Dhaka, Chattogram, Rajshahi, Khulna, Barishal, Sylhet, Rangpur, Mymensingh.

Sundarbans is the world's largest mangrove forest, a UNESCO World Heritage Site (1997), home of the Royal Bengal Tiger.

Cox's Bazar hosts the world's longest natural sandy sea beach (~120 km); Saint Martin's is Bangladesh's only coral island.

Bangladesh is a riverine delta formed by the Ganges–Brahmaputra–Meghna; largest river by width is the Meghna.

Bangladesh joined the United Nations in 1974; SAARC founded in Dhaka in 1985; headquarters of BIMSTEC is in Dhaka.

Padma Bridge opened 25 June 2022, connecting southwestern districts to the capital.

United Nations founded 24 October 1945; headquarters in New York; 193 member states; Security Council has 5 permanent members with veto.

Specialized UN agencies: WHO (Geneva), UNESCO (Paris), FAO (Rome), ILO (Geneva), UNICEF (New York), IMF and World Bank (Washington, DC).

SAARC founded 1985 in Dhaka, 8 members; ASEAN founded 1967 in Bangkok, 10 members; OIC founded 1969 in Rabat, 57 members.

European Union established by Maastricht Treaty (1993); euro currency introduced 1999; Nobel Peace Prize 2012.

G7 comprises USA, UK, France, Germany, Japan, Italy, Canada; G20 includes major economies and the EU.

Bretton Woods Conference (1944) created the IMF and the World Bank; both began operations in 1945–46.

Non-Aligned Movement founded at Belgrade (1961) after the Bandung Conference (1955).

Cold War ended with the dissolution of the Soviet Union in December 1991.

SI base units: metre (length), kilogram (mass), second (time), ampere (current), kelvin (temperature), mole (amount), candela (luminous intensity).

Newton's laws: inertia (F=0 → constant velocity), F = ma, action–reaction pairs equal and opposite.

Photosynthesis: 6CO₂ + 6H₂O + light → C₆H₁₂O₆ + 6O₂, occurring in chloroplasts using chlorophyll.

Human blood groups ABO and Rh; universal donor O−, universal recipient AB+; heart has four chambers.

DNA double helix described by Watson and Crick (1953); base pairing A–T, G–C.

Periodic table groups: alkali metals (Group 1), halogens (Group 17), noble gases (Group 18).

Speed of light in vacuum ≈ 3 × 10⁸ m/s; acceleration due to gravity g ≈ 9.8 m/s².

Vaccines work by stimulating antibody production; antibiotics target bacteria, not viruses.

Greenhouse gases include CO₂, CH₄, N₂O, water vapour, and CFCs; CO₂ is the largest anthropogenic contributor.

Computer generations: 1st vacuum tubes, 2nd transistors, 3rd integrated circuits, 4th microprocessors, 5th AI.

Binary to decimal: multiply each bit by 2^position from right; 1011₂ = 11₁₀.

Memory hierarchy: registers > cache > RAM > secondary storage, by speed and cost.

OSI model has 7 layers: Physical, Data Link, Network, Transport, Session, Presentation, Application; TCP/IP has 4.

IPv4 uses 32-bit addresses; IPv6 uses 128-bit addresses.

HTTP (port 80), HTTPS (443), FTP (21), SMTP (25), DNS (53), SSH (22).

1 byte = 8 bits; 1 KB = 1024 bytes; 1 MB = 1024 KB; 1 GB = 1024 MB.

SQL is a declarative query language; primary key uniquely identifies rows; foreign key references another table's primary key.

Malware categories: virus (needs host), worm (self-replicating), trojan (disguised), ransomware (encrypts and demands payment).

Core values: honesty, integrity, accountability, transparency, fairness, respect for rule of law.

Good governance characteristics (UNDP): participation, rule of law, transparency, responsiveness, consensus orientation, equity, effectiveness, accountability.

Corruption types include bribery, embezzlement, nepotism, extortion, and conflict of interest.

Transparency International publishes the Corruption Perceptions Index (CPI) ranking countries by perceived public-sector corruption.

Conflict of interest arises when private interest interferes with public duty; recusal is the standard remedy.

Whistleblowing is disclosure of wrongdoing; protections vary by jurisdiction and organization.

Code of conduct typically covers gifts, confidentiality, use of public resources, and political neutrality.

Bangladesh's Anti-Corruption Commission (ACC) was established in 2004 under the Anti-Corruption Commission Act.

Earth's layers: crust (continental ~35 km, oceanic ~7 km), mantle, outer core (liquid), inner core (solid iron-nickel).

Latitude lines run east–west; longitude lines run north–south; 1° latitude ≈ 111 km.

Tropic of Cancer (23.5°N) and Tropic of Capricorn (23.5°S) mark the tropics; equator is 0°.

Bangladesh lies between 20°34′N–26°38′N and 88°01′E–92°41′E; area ≈ 147,570 km².

Rivers of Bangladesh: Padma, Meghna, Jamuna, Brahmaputra, Karnaphuli (only major river rising within Bangladesh).

Climate of Bangladesh: tropical monsoon; seasons summer (Mar–May), monsoon (Jun–Sep), autumn, winter (Dec–Feb).

Highest peak globally: Mount Everest (8,849 m); Bangladesh's highest point is Keokradong (~1,230 m).

Largest ocean is the Pacific; deepest trench is the Mariana Trench (~11,000 m).

Soil types: alluvial (most of Bangladesh), red soil (Chittagong Hill Tracts), peat, coastal saline.

Greenhouse effect: trapped infrared radiation by atmospheric gases warms Earth; enhanced by anthropogenic emissions.

Ozone layer in the stratosphere absorbs UV-B; depleted by CFCs and halons; Montreal Protocol (1987) phases them out.

Kyoto Protocol (1997) set binding targets for developed countries; Paris Agreement (2015) targets ≤2°C warming, ideally 1.5°C.

Disaster cycle: mitigation, preparedness, response, recovery; Bangladesh uses a cyclone early-warning system and cyclone shelters.

Bangladesh is highly vulnerable to cyclones, floods, riverbank erosion, and salinity intrusion due to low elevation and dense population.

Biodiversity hotspots: Sundarbans (mangrove), Chittagong Hill Tracts; Ramsar sites include Tanguar Haor.

EIA (Environmental Impact Assessment) evaluates project impacts before approval; SEA applies at policy level.

Reduce, reuse, recycle (3R) hierarchy; waste segregation at source improves recycling efficiency.

Sendai Framework (2015–2030) sets global disaster risk reduction priorities: understanding risk, governance, investment, preparedness.