Computer Science Previous Year Questions (page 43)

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cin.ignore(x, y) discards up to x characters from the input, or stops earlier once the delimiter character y has been read and discarded.

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A page fault occurs when a program refers to a page that is not currently in main memory. The OS then loads it from secondary storage.

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Cash or goods withdrawn by the owner for personal use are called drawings. They reduce the owner's capital.

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The href attribute of the <a> tag gives the destination URL of a hyperlink, as in <a href="page.html">.

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A try block can be followed by many catch blocks but at most one finally block. A try with only a finally (no catch) is also allowed, so A is wrong.

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32 KB / 1 KB = 32 blocks, and with 4 ways that is 8 sets (3 set bits). The block offset is 10 bits and the address is 35 bits (32 GB = 2³⁵ bytes). Tag = 35 − 3 − 10 = 22 bits.

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The CMOS memory that stores BIOS settings is kept powered by a small coin-cell battery on the motherboard. POST runs at power-on (not shutdown), and bootstrap code is in ROM.

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T = 2π√(x/g), so the extension x = gT²/4π² = 9.8 × 0.36 / 39.48 ≈ 0.089 m. The spring shortens by this amount when the mass is removed.

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/usr holds user programs, libraries and documentation. Temporary files are kept in /tmp.

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Elasticity of demand measures the degree (extent) of responsiveness of quantity demanded to a change in price.

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FORTRAN stands for FORmula TRANslation. It was developed by IBM (John Backus) in 1957 for scientific computing.

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In a path graph the two end vertices have degree 1 and every other vertex has degree 2, so n − 2 vertices have degree 2.

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In the source's classification, businesses are experience driven, efficiency driven or expert driven. "Expense driven" is not one of the types.

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For the arithmetic mean, Σ(x − x̄) = 0, so the sum of deviations measured from the mean is always zero.

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All-pairs shortest path (Floyd-Warshall) is solved by dynamic programming. Binary search, quick sort and Strassen's multiplication are divide and conquer algorithms.

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The plane x/a + y/b + z/c = 1 meets the axes at a, b and c. The tetrahedron's volume = (1/3) × (ab/2) × c = abc/6.

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target="_top" opens the link in the full body of the window and breaks out of all frames. _blank opens a new window, and _parent opens it in the parent frame.

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S1 has R1(B) before W2(B) (T1→T2) and R2(A) before W1(A) (T2→T1), which forms a cycle. S2 only has edges T2→T1, so it is conflict serializable (equivalent to T2, T1).

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An external stylesheet is linked in the <head> with <link rel="stylesheet" type="text/css" href="style.css">.

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jQuery's slideDown() shows a hidden element with a sliding-down animation. slideUp() hides it and slideToggle() switches between the two.

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Liang-Barsky is a parametric line-clipping algorithm. DDA, Bresenham and the mid-point algorithm are line or circle drawing algorithms.

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Under the double-entry system, every transaction has two aspects, a debit and a credit, of equal amounts.

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New files are created with 666 permissions, and the default umask 022 turns that into 644, which is rw-r--r--.

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When a mobile station enters a new area, the serving VLR registers it and informs the HLR of the location change, so the HLR always knows which VLR area the subscriber is in.

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Eg = hc/λ = 12400 eV·Å / 5511.11 Å ≈ 2.25 eV.

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The waterfall model is simple and considered low cost for well-defined projects, but it takes long and carries high risk. So "high cost" is the statement that is not true of it.

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Pseudo-code is already written in structured, code-like statements, so it is the easiest to turn directly into a program.

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Growth order: log n < n < n log n < n² < n² log n < 2ⁿ. Exponential growth is the fastest.

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The CSS filter grayscale(100%) makes an image completely black and white, so the rule is img { filter: grayscale(100%); }.

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grep (global regular expression print) searches files for a pattern and prints the matching lines. tr changes case, cut extracts columns, and a pipe redirects output.

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DOM, SAX and JDOM are XML parsers or APIs. Shell is a command interpreter, not an XML parser.

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The effect of lighting depends on the light source, the surface's properties and the observer's position. The rendering algorithm is a technique for drawing the scene, not a lighting parameter.

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4 KB = 4 × 1024 = 4096 bytes, not 4069. The others are right: 5 KB = 10,240 nibbles, 3 KB = 24,576 bits and 2 KB = 4096 nibbles.

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Δe^(ax+b) = e^(a(x+h)+b) − e^(ax+b) = (e^(ah) − 1)e^(ax+b). Applying Δ n times gives (e^(ah) − 1)ⁿ e^(ax+b).

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Cascading counters multiplies their moduli: 6 × 8 = 48, giving a Mod-48 counter.

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Complementing one input of an XOR complements the whole result: A ⊕ (B ⊙ C) = A ⊕ (B ⊕ C)' = (A ⊕ B ⊕ C)'. That is the complement of the three-variable function.

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An external DTD is declared as <!DOCTYPE root-element SYSTEM "file-name">, where the root element name comes before SYSTEM and the file path.

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PQ⁺: P → RT adds R and T, and Q → S adds S. QS → TU then adds U, so PQ⁺ = PQRSTU (PQ is a key).

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Check 8x² − 19x + 12: at x = 1 it gives 1, at x = 3 it gives 72 − 57 + 12 = 27, and at x = 4 it gives 128 − 76 + 12 = 64. It matches all three points.

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A sum of 5 occurs 4 ways and a sum of 9 occurs 4 ways out of 36, so P(5 or 9) = 8/36 = 2/9. The required probability is 1 − 2/9 = 7/9.

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Separating variables gives e^(−y) dy = e^x dx. Integrating gives −e^(−y) = e^x + k, so e^x + e^(−y) = c.

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Transport-layer flow control (with acknowledgements and retransmission) stops a fast sender from overwhelming the receiver, which prevents data loss.

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Descriptive attributes belong to a relationship set and record information about the relationship itself, such as the date a student enrolled in a course.

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TCP is connection-oriented (it uses a three-way handshake), so calling it connection-less is false. UDP is the connection-less protocol.

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Packages do provide controlled access through package-private (default) and protected access. They also prevent naming conflicts and support encapsulation.

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In slow start, cwnd grows by 1 MSS for each ACK, which roughly doubles the window every round-trip time until it reaches the threshold.

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A knowledge management system aims at capturing and sharing knowledge, integration and supporting strategy. Portability is not one of its purposes.

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Per the key, system software is traditionally written in a low-level (assembly or machine-oriented) language for close hardware control, while application software is written in high-level languages.

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C shell, Korn shell and Bourne shell are Unix/Linux shells. "Alpha cell" is not a shell.

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Fifth-generation languages, such as Prolog, solve problems using constraints and logic rules instead of step-by-step algorithms. Java, COBOL and Python are third-generation languages.