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InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 251. |
Which of the following statements with respect to electrochemical principles of metallurgy are not correct?A. In simple electrolysis, the `M^(n^(+))` ions are discharged at positive electrodesB. More reactive metals have large neagative values of the electrode potential, thus their reducttion is difficultC. Positive `E^(0)`, results in negative `DeltaG`, the reaction would be spontanous, thus less reactive metal will come out of the solution and nore reactive metal will go into the solutionD. If for a cell reaction `E^(0)` is negative, the value of `DeltaG`, for the cell reaction would be +ve and the reaction would not be feasible. |
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Answer» Correct Answer - 1 |
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| 252. |
Match the conversions in Column I with the type(s) of reaction(s) given in Column II. `{:("Column I","ColumnII"),(A. "PbS"rarr"PbO",p. "Roasting"),(B. "CaCo"_(3)rarr"CaO",q. "Calcination"),(C. "ZnS"rarr"Zn",r. "Carbon reduction"),(D. "Cu"_(2)"S"rarr"Cu",s. "Self-reduction"):}`A. a-q: b-r : c-p,r :d-p,sB. a-p:b-q:c-p,r: d-p,sC. a-p,s: b-q : c-p : d-sD. a-p, s: b-p,q : c-p: d-s |
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Answer» Correct Answer - B |
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| 253. |
For the reduction of `FeO` at the temperature corresponding to point D, which of the following statements is correct?A. ?G value for the overall reductioon reaction with carbon monoxide is zeroB. ?G value for the overall reductioon reaction with a mixture of 1 mol carbon and 1 mol oxygen will be positiiveC. ?G value for the overall reductioon reaction with a mixture of 2 mol carbon and 1 mol oxygen will be positiiveD. ?G value for the overall reductioon reaction with carbon monoxide is negative |
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Answer» Correct Answer - 1 |
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| 254. |
Which occurs to minmum extent in natureA. `Ag_(2)S`B. `H_(2)S`C. `Bi_(2)S_(3)`D. `Cs_(2)` |
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Answer» Correct Answer - d |
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| 255. |
Extraction of copper is done using copper pyrites. After roasting, the ore is mixed with silica and coke and then smelted in a blast furnace. The matte obtained from the blast furnace is charged into a silica-lined converter. Some silica is also added, and a hot air blast is blown into the mixture to obtain blister copper, which is purified by electrorefining. Coke is added during smelting to.A. To reduce FeO to Fe.B. to reduce `Cu_(2)O` to CuC. to check the oxidation of FeO to `Fe_(2)O_(3)`D. To check the reduction of FeO |
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Answer» Correct Answer - c |
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| 256. |
Extraction of copper is done using copper pyrites. After roasting, the ore is mixed with silica and coke and then smelted in a blast furnace. The matte obtained from the blast furnace is charged into a silica-lined converter. Some silica is also added, and a hot air blast is blown into the mixture to obtain blister copper, which is purified by electrorefining. The chemical formula of copper pyrites is.A. `CuFeS_(2)`B. `Cu_(2)S`C. `Cu_(2)O`D. `CuCO_(3).Cu(OH)_(2)` |
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Answer» Correct Answer - a |
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| 257. |
Formation of which of the sulphides is most spontaneous?A. HgSB. `Bi_(2)S_(3)`C. PbSD. `Cs_(2)` |
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Answer» Correct Answer - c |
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| 258. |
`FeCr_(2)O_(4)+NaOH+"air" to (A)+Fe_(2)O_(3)` `(A)+(B) to Na_(2)Cr_(2)O_(7)` `Na_(2)Cr_(2)O_(7)+X overset(Delta)to Cr_(2)O_(3)` `Cr_(2)O_(3)+Y overset(Delta)to Cr` (X) and (Y) are :A. Dissolving in conc ,`H_(2)SO_(4)`B. Dissolving in `NH_(3)`C. Dissolving in `H_(2)O`D. Dissolving in dil,HCl |
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Answer» Correct Answer - a |
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| 259. |
which of the following sulphides cannot be reduced to metal by `H_(2)`at about `1000^(@)`C?A. HgSB. PbSC. `CS_(2)`D. `Bi_(@)S_(3)` |
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Answer» Correct Answer - b |
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| 260. |
`FeCr_(2)`(chromite ) is a good soure of chromium and its compounds like `Na_(2)CrO_(4),Na_(2)Cr_(2)O_(7)`` P:FeCr_(2)O_(4)+NaOH+airto A+Fe_(2)O_(3)Q:` `A+Bto Na_(2)Cr_(2)O_(7)``R:Na_(2)Cr_(2)O_(7)+Xoverset(Delta)toCr_(2)O_(3)``S:Cr_(@)O_(3)+YtoCr` COmpounds (A) and(B)are:-A. `Na_(2)Cr.O_(4),H_(2)SO_(4)`B. `Na_(2)Cr_(2)O_(7),HCl`C. `Na_(2)CrO_(5),H_(2)SO_(4)`D. `Na_(4)[Fe(OH)_(6)],H_(2)SO_(4)` |
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Answer» Correct Answer - a |
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| 261. |
`FeCr_(2)`(chromite ) is a good soure of chromium and its compounds like `Na_(2)CrO_(4),Na_(2)Cr_(2)O_(7)`` P:FeCr_(2)O_(4)+NaOH+airto A+Fe_(2)O_(3)Q:` `A+Bto Na_(2)Cr_(2)O_(7)``R:Na_(2)Cr_(2)O_(7)+Xoverset(Delta)toCr_(2)O_(3)``S:Cr_(@)O_(3)+YtoCr` (X)and (Y) are:A. Aland CB. C and AlC. C in bothD. Al in both |
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Answer» Correct Answer - b |
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| 262. |
Tin and lead can be refined byA. LiquationB. cupellationC. PolingD. Bessemerisation |
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Answer» Correct Answer - 1 |
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| 263. |
Which among the following is a basic fluxA. BoraxB. CaOC. `SiO_(2)`D. `P_(2)O_(5)` |
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Answer» Correct Answer - 2 |
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| 264. |
Identify the incorrect statement from the following in froth floatation methodA. Froth carries the mineral particlesB. Froth carries gangue particlesC. Froth collectors enhance the non-wettability of the mineral particle with waterD. The mineral particles become wet by oils while gangue become wet by water. |
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Answer» Correct Answer - 2 |
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| 265. |
Which of the following is a froth stablizer in the frothfloatation process?A. Fatty acidsB. AnilineC. pine oilD. Xanthates |
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Answer» Correct Answer - 2 |
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| 266. |
Which of the following acts as "activator" in the foth flotation process?A. KCNB. NaCNC. Sodium ethyl XanthalateD. Copper sulphate |
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Answer» Correct Answer - 4 |
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| 267. |
Tarnishing of silver is due to the formation ofA. `Ag_(2)S`B. `Ag_(2)O`C. AgClD. `Ag_(2)SO_(4)` |
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Answer» Correct Answer - 1 |
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| 268. |
Which of the following is not added during the extraction of silver by cyanide process?A. NaCNB. AirC. ZnD. `Na_(2)S_(2)O_(3)` |
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Answer» Correct Answer - 4 |
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| 269. |
Zinc dust is obtained byA. crushing zinc metalB. Burning zinc metal in airC. Melting zinc and then atomising it with a blast of airD. Roasting zinc sulphide. |
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Answer» Correct Answer - 3 |
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| 270. |
Cost iron is prepared from haematite . In most of the Cases ore needs no concentration ,The ore is roasted to remove the volatile impurities ,During roasting the ,mass becomes porous Iron in the form of ferrous oxide os mixed with coke and heated in a blast furnace ,pig iron ios formed and is casted in the desired shape. One of the important advantages of rosting the iron ore isA. Wastage of ore in the form of `FeSiO_(3)` is avoidedB. Was tage of one in the form of `Fe_(2)(SiO_(3))_(3)` is avidedC. Ferrous oxide is removed as mot=lten slag `FESiO_(3)`D. Ferric oxide is removed as molten slag `Fe_(2)(SiO_(3))_(3)` |
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Answer» Correct Answer - a |
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| 271. |
How many water molecules are associated with Epsom salt? |
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Answer» Correct Answer - 7 |
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| 272. |
Hydro metallurgy is used in the extraction ofA. CuB. AuC. AgD. All |
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Answer» Correct Answer - D |
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| 273. |
Highly electropositive metals can not be extracted by carbon reduction process because these :A. Metals combine with carbon to form carbidesB. Metals do not react with carbonC. Metals oxides are not reduced by carbonD. Loss of metal is more by vaporisation |
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Answer» Correct Answer - a,d |
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| 274. |
The funciton of adding cryolite in the electrolytic reduction of alumina by Hall-Heroult process is to :A. dissolve aluminaB. lower the melting point of aluminaC. lower the fuel billD. increase the electrical canductivity of alumina |
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Answer» Correct Answer - a,b,c,d |
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| 275. |
Zone refining is based on the principle ofA. fractional distillationB. fractional crystallisationC. partition coefficentD. chromatographic seperation |
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Answer» Correct Answer - 2 |
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| 276. |
Which of the following statements is false?A. During roasting moisture is removed from the oreB. The ore is freed from almost all non-metallic impuritiesC. Calcination of ore is called is carried out in absence of any blast of airD. The concentrated zinc blende is subjected to calcinaiton during its extraction by pyrometalllurgy |
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Answer» Correct Answer - 4 |
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| 277. |
The most electropositive metal are isolated from their ores byA. High temperature reduction with carbonB. Self reductionC. Thermal decompositionD. Electrolysis of fused ionic salts |
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Answer» Correct Answer - 4 |
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| 278. |
The most electropositive metal among the following isA. ZnsB. FeC. CaD. Na |
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Answer» Correct Answer - 4 |
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| 279. |
Lodstone used by ancient mariners to find the direction isA. `Fe_(2)O_(3)`B. `Fe_(3)O_(3)`C. FeD. `FeS_(2)` |
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Answer» Correct Answer - 2 |
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| 280. |
Nitriding is a process of hardening steel by treating it inan atmosphere ofA. ammoniaB. oxygenC. carbondioxideD. air |
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Answer» Correct Answer - 1 |
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| 281. |
Assertion : `PbSiF_(6)+H_(2)SiF_(6)+` gelatine is taken as electrolyte in electrolytic refining of lead. Reason : Discharge potential of `Pb^(2+)` is less than `H^(+)`.A. Statement - 1 is true , Statement -2 is True , Statement -2 is a correct explanation for statement -1B. Statement -1 : is true , Statement-2 is true , Statement -2 : Not a correct explanation for statement - 1C. Statement-1 : is true , Statement -2 is false ,D. Statement-1 : is false , statement-2 : is true |
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Answer» Correct Answer - c |
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| 282. |
When Bauxite is heated with NaOH solution, the water soluble compound formed isA. `NaAlO_(2)`B. `Na_(3)AlO_(3)`C. `Al(OH)_(3)`D. `Al_(2)O_(3)` |
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Answer» Correct Answer - A |
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| 283. |
Cast iron contains phosphorus as impurity. In Bessemerisation of this cast iron the slag formed isA. `FePO_(4)`B. `Ca(PO_(4))_(2)`C. `MnPO_(4)`D. `Zn_(3)(PO_(4))_(2)` |
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Answer» Correct Answer - B |
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| 284. |
In the electrolusis of alumina. Cryolite is absorbed toA. Lower that melting point of alumiaB. Increase the electical condivityC. Minimise the anode effectD. Remove impurities form alumia |
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Answer» Correct Answer - B |
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| 285. |
Which of the following is not a correct statement ?A. What cast iron contains carbon in the form of `Fe_(3)C`B. Grey cast iron contains carbon in the form of graphite.C. The quality of steel produced in Bessemer converter is very highD. The quality of steel produced in open hearth process can be checked from time to time. |
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Answer» Correct Answer - C |
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| 286. |
Ultrapure elements are obtained in the following method of mental refiningA. ElectrolysisB. PolingC. LiquationD. Distallation |
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Answer» Correct Answer - D |
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| 287. |
Which of the following statement is true?A. Reduction of a metal oxide is easier if the metal formed is in liquid state at reduction temperatureB. Reduction of metal oxide is metal oxide is normally less feasible at high temperatureC. The oxidation of CO into `CO_(2)` will have a negative slope on Ellingham diagramD. The reactive metals have positive slope for oxidation on Ellingham diagram where as nonreactive metals have a neative slope |
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Answer» Correct Answer - A |
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| 288. |
In the elctrolysis of alumina using cryotile, the reaction that takes place at cathode isA. `12F^(-) to 6 F_(2)+12e^(-)`B. `4H_(2)O+4e^(-) to 2H_(2)+4OH^(-)`C. `6F_(2)+2Al_(2)O_(3) to 4AlF_(3)+3O_(2)`D. `4Al^(3+)+12e^(-) to 4Al` |
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Answer» Correct Answer - D |
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| 289. |
The function of fluorspar in the electrolytic reduction of alumnia dissolved in fused cryotile `(Na_(3)AlF_(6))` is:A. as a catalystB. to lower the temperature of the melt and improve the condivity of cellC. to decrease the rate of oxidation of carbon at the cathodeD. to decrease the rate of oxidation of carbon at the cathode |
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Answer» Correct Answer - B |
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| 290. |
(A) Au,Pt,Ag etc are found in free state (R ) The metals which are noble and chemically less reactive are found in free stateA. If both (A) and (R ) are correct and (R ) is the correct explantion of (A )B. If both (A) and (R ) are correct and (R ) is not the correct explantion of (A )C. If (A) is correct but (R ) is incorrectD. If (A) is incorrect but (R ) is correct |
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Answer» Correct Answer - A |
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| 291. |
Which of the following is its mineral for tinA. GalenaB. CerussiteC. CassiteriteD. Angesite |
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Answer» Correct Answer - C |
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| 292. |
In the extraction of chlorine from brine_________A. ?`G^(T)` for the overall reaction is negative .2B. ?`G^(T)` for the overall reaction is positiveC. ?`E^(T)` for the overall reaction has negative valueD. ?`E^(T)` for the overall reaction has positive value |
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Answer» Correct Answer - 2,3 |
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| 293. |
Metal refined by cupellation process isA. AgB. FeC. ZnD. Sn |
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Answer» Correct Answer - A |
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| 294. |
Silver is refined by cupellation process, the process removes the impurity of:A. CuB. AuC. PbD. Pt |
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Answer» Correct Answer - 3 |
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| 295. |
Zone refining is a method to obtainA. very high temperatureB. ultra pure AlC. ultra pure metalsD. ultra pure oxides |
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Answer» Correct Answer - C |
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| 296. |
Which one of the following elements is present as a major impurity in pig iron ?A. graphiteB. oxygenC. sulphurD. silicon |
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Answer» Correct Answer - 1 |
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| 297. |
Spelter is impure form ofA. ZnB. AgC. CuD. Fe |
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Answer» Correct Answer - A |
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| 298. |
In the extraction of copper the smelt formed in the blast furnace contiansA. `CuS+"little"FeS`B. `Cu_(2)S+"little"FeO`C. `Cu_(2)O+"little"FeS`D. `Cu_(2)O+"little"FeO |
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Answer» Correct Answer - A |
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| 299. |
Which of the following metal is refined by distaillation methodA. ZincB. IronC. TinD. Copper |
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Answer» Correct Answer - A |
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| 300. |
Zone refining method is used for refiningA. AlB. GeC. CuD. Fe |
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Answer» Correct Answer - B |
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