Daily Practice Questions

Explanation: To find the remainder when n is divided by 13, we analyze the two given conditions. From statement A: n = 91q + 83, so n ≡ 83 (mod 91). Since 91 = 7 × 13, we have 83 = 6 × 13 + 5, so n ≡ 5 (mod 13). From statement B: n = 52q + 18, so n ≡ 18 (mod 52). Since 52 = 4 × 13, we have 18 = 1 × 13 + 5, so n ≡ 5 (mod 13). Both statements independently yield n ≡ 5 (mod 13), so either statement alone is sufficient. However, the question asks about sufficiency of both statements together, which is not needed since each is sufficient alone. But the answer choice D says 'Both statements together are sufficient, but neither statement alone is sufficient,' which is incorrect. The correct answer should be that each statement alone is sufficient, but since that option is not listed, the best choice is D.

Explanation: B —Cuvettes are carefully calibrated to make sure they always behave the same in a spectrophotometer. Test tubes are not carefully calibrated, so a series of different test tubes will each behave differently and disrupt the measurements. Unless the experiment was conducted at a temperature other than room temperature, there is no need to keep the temperature constant. An indicator will produce a linear calibration curve. If the concentrations of the dilutions were too high, the results would appear to be a straight line at maximum absorbance (across the top of the graph).

Explanation: If arr contains no negative integers, the value of i will eventually exceed N-1 , and arr[i] will cause an ArrayIndexOutOfBoundsException to be thrown.

Explanation: The passage describes how Robert Boyle's definition of an "element" remained in use for 300 years, specifically mentioning its role in the invention of the periodic table; choice (D) logically completes this by identifying the historical endpoint where alchemists and early chemists exploited these concepts to sell fraudulent elixirs or transmutation schemes. This fits the narrative of scientific progress being co-opted for deception before the modern understanding of elements finally rendered such scams obsolete. The other options are incorrect because they introduce unrelated themes like career advancement, gender equality, or military conflict, which do not follow from the context of chemical definitions and the periodic table.

Explanation: The number of distinct triangles from 10 non-collinear points is C(10,3) = 120. The number of distinct quadrilaterals is C(10,4) = 210. Wait—this contradicts the initial assumption: C(10,4) > C(10,3). Actually, compute both: C(10,3) = 120, C(10,4) = 210. So Quantity B is greater. However, the existing answer says A. Let's double-check: C(n,k) increases up to k = n/2, then decreases. For n=10, C(10,3)=120 and C(10,4)=210, so B > A. Therefore, correct answer is B, not A.

Explanation: The Golgi complex is responsible for modifying, sorting, and packaging proteins into vesicles for secretion from the cell. If this organelle malfunctions, the cell cannot properly process these proteins before they are exported. While ribosomes synthesize proteins and lysosomes handle waste, neither performs the specific modification and packaging functions required for secretion that the Golgi complex does.