UPSC Combined Defence Services · Past-year questions with answers

Insurance is in the Union List (Entry 47), so the statement that it is not a Union subject is wrong. In the Seventh Schedule, insurance is Entry 47 of the Union List; taxes on agricultural income are Entry 46 of the State List; price control is Entry 34 of the Concurrent List; and forests became a Concurrent subject (Entry 17A) under the 42nd Amendment, 1976.

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Per capita GDP equals the working-age share times the work participation rate times output per worker, so all three matter. GDP per person can be written as (working-age population ÷ total population) × (workers ÷ working-age population) × (GDP ÷ workers). Each factor, the share of working-age people, the proportion of them actually working and the productivity of each worker, therefore affects per capita GDP.

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Navigation and laying of submarine cables are freedoms open to all states in the EEZ, not exclusive coastal-state rights. Under the UN Convention on the Law of the Sea, a coastal state has sovereign rights in its exclusive economic zone for exploring, exploiting, conserving and managing natural resources, living or non-living, and for activities such as producing energy from water, currents and winds. All other states keep the freedoms of navigation, overflight and laying of submarine cables and pipelines in the zone.

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Two coprime reduced pairs yield different differences, so the data do not fix one answer. Let HCF=q and LCM=14q. Their product gives 14q²=1134, so q=9 and LCM=126. Coprime reduced pairs can be (1,14) or (2,7), giving numbers (9,126) or (18,63), with differences 117 and 45. The difference is not unique.

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Temperature and actual moisture content are both needed for relative humidity. Relative humidity compares actual water vapour with the saturation value at the same temperature. Actual moisture content and temperature are both needed to determine that comparison.

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Only the Fifth Schedule pairing is correct. Only pair 3 is correct. The First Schedule lists states and Union territories; the Third contains oath forms; the Fourth allocates Rajya Sabha seats; the Fifth concerns Scheduled Areas and Scheduled Tribes; the Sixth concerns specified tribal areas. The Ninth is associated with protected enactments, not tribal administration.

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In an isotonic solution there is no net water movement, so RBCs keep their size. Normal saline (0.9% sodium chloride) has the same solute concentration as blood plasma. Water enters and leaves the red cells at equal rates, so they neither swell nor shrink.

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The remaining half-lap places the boy one diameter, 200 m, from the start. The time is 225 s, or 225/30=7.5 revolutions at uniform speed. After seven complete rounds and a half-round, the boy is diametrically opposite his start, so displacement magnitude equals the 200 m diameter.

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The tower extends 3h above the deck, making its total height 4h. Let horizontal distance be d and tower height H. The depression angle gives h/d=tan30°=1/√3, so d=h√3. Elevation gives (H−h)/d=√3, hence H−h=3h and H=4h.

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S2 accepts that failure can lead to success but limits it: repeated failures are not repeated steps, so S2 qualifies S1. S1 states a proverb: failure is a stepping stone to success. S2, introduced by 'however', does not reject this; it adds that 'Successive failures' are not 'successive stepping stones to success'. Adding a condition or limit to a statement without denying it is to 'qualify' it.

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A Navy Captain is equivalent to an Air Force Group Captain. Captain in the Navy, Colonel in the Army and Group Captain in the Air Force are equivalent ranks. The same word Captain in the Army denotes a much lower rank.

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The initial one-third of the tank takes all three taps 2 hours. All three taps fill 1/6 tank per hour and C fills 1/12, so A+B fill 1/12. Eight hours after C closes supplies 8/12=2/3 tank; the initial 1/3 tank takes (1/3)/(1/6)=2 hours.

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'Evade' means to escape or avoid and takes a direct object: 'managed to evade capture'. 'Evade' means to escape from or avoid, often by cunning, and takes a direct object, so 'managed to evade capture' is the standard collocation for a fugitive. Completed sentence: 'The criminal on the run managed to evade capture by the police officer.'

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The Vajji confederacy, with its capital at Vaishali, was a gana-sangha ruled by assemblies of clan heads. Among the sixteen mahajanapadas, most were monarchies, but some, such as the Vajji confederacy (including the Lichchhavis) of north Bihar, were ganas or sanghas governed collectively by a group of rulers.

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Fidel Castro was not among the founding core of NAM, which centred on Nehru, Nasser, Tito, Sukarno and Nkrumah. The Non-Aligned Movement took shape at the Belgrade Conference of 1961, with Jawaharlal Nehru, Gamal Abdel Nasser, Josip Broz Tito, Sukarno and Kwame Nkrumah as its leading figures. Fidel Castro became prominent in the movement later and chaired it from 1979.

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AM 20 and GM 16 give a difference of 24. AM=40/2=20 and GM=0.8×20=16, so xy=256. Then (x−y)²=(x+y)²−4xy=1600−1024=576. The positive difference is 24.

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Alluvial soils vary in sand, silt and clay, are rich in potash, phosphoric acid and lime, and are divided by age into khadar and bhangar. Alluvial soils are deposited by rivers, so their texture ranges through sand, silt and clay. They generally contain adequate potash, phosphoric acid and lime, and they are classified by age into the older bhangar and the newer khadar.

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'What would you do' is the result clause of a second conditional, so the if-clause takes the simple past: 'if you won a lot of money'. The completed sentence is 'What would you do if you won a lot of money?' A hypothetical present or future situation uses 'would' in the main clause and the past simple in the if-clause.

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An inradius of 4 cm gives incircle area about 50.27 cm². The triangle is right-angled because 12²+16²=20². Its area is 96 cm² and semiperimeter is 24 cm, so inradius=area/semiperimeter=4 cm. The incircle area is 16π≈50.27 cm².

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To 'make heavy weather of' something is to make a task seem harder than it is, dealing with it with needless difficulty. To 'make heavy weather' of a task means to make it more difficult or laborious than it need be, often with a lot of fuss. The image is of a vessel struggling through rough weather. Option (d), 'Unnecessarily create difficulty in dealing with a task', states this meaning.

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