# Recent activity by Subarna Das

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On a TCP connection, current congestion window size is Congestion Window = $4$ KB. The window size advertised by the receiver is Advertise Window = $6$ KB. The last byte sent by the sender is LastByteSent = $10240$ and the last byte acknowledged by the receiver is LastByteAcked = $8192$. The current window size at the sender is: $2048$ bytes $4096$ bytes $6144$ bytes $8192$ bytes
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We wish to construct a $B^+$ tree with fan-out (the number of pointers per node) equal to $3$ for the following set of key values: $80, 50, 10, 70, 30, 100, 90$ Assume that the tree is initially empty and the values are added in the order given. Show ... Intermediate trees need not be shown. The key values $30$ and $10$ are now deleted from the tree in that order show the tree after each deletion.
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Consider the depth-first-search of an undirected graph with $3$ vertices $P$, $Q$, and $R$. Let discovery time $d(u)$ represent the time instant when the vertex $u$ is first visited, and finish time $f(u)$ represent the time instant when the vertex $u$ ... connected There are two connected components, and $Q$ and $R$ are connected There are two connected components, and $P$ and $Q$ are connected
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In the figure below, $\angle DEC + \angle BFC$ is equal to _____ $\angle BCD - \angle BAD$ $\angle BAD + \angle BCF$ $\angle BAD + \angle BCD$ $\angle CBA + \angle ADC$
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Let $m, n$ be positive integers with $m$ a power of $2$. Let $s= 100 n^{2} \log m$. Suppose $S_{1}, S_{2},\dots ,S_{m}$ are subsets of ${1, 2, \dots, s}$ such that $\mid S_{i} \mid= 10 n \log m$ and $\mid S_{i} \cap S_{j} \mid \leq \log m$ for all $1 \leq i \lt j \leq m$. Such a ... $0.9$ if $x ∉ T$. $1$ if $x \in T$ and at least $0.9$ if $x ∉ T$. At least $0.9$ if $x \in T$ and $1$ if $x ∉ T$.
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Consider the differential equation $dx/dt= \left(1 - x\right)\left(2 - x\right)\left(3 - x\right)$. Which of its equilibria is unstable? $x=0$ $x=1$ $x=2$ $x=3$ None of the above.
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A class of twelve children has two more boys than girls. A group of three children are randomly picked from this class to accompany the teacher on a field trip. What is the probability that the group accompanying the teacher contains more girls than boys? $0$ $\dfrac{325}{864}$ $\dfrac{525}{864}$ $\dfrac{5}{12}$
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Two alloys $A$ and $B$ contain gold and copper in the ratios of $2:3$ and $3:7$ by mass, respectively. Equal masses of alloys $A$ and $B$ are melted to make an alloy $C$. The ratio of gold to copper in alloy $C$ is ______. $5:10$ $7:13$ $6:11$ $9:13$
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A two-way switch has three terminals $a, b$ and $c.$ In ON position (logic value $1$), $a$ is connected to $b,$ and in OFF position, $a$ is connected to $c$. Two of these two-way switches $S1$ and $S2$ are connected to a bulb as shown below. Which of the following ... , if true, will always result in the lighting of the bulb ? $S1.\overline{S2}$ $S1 + S2$ $\overline {S1\oplus S2}$ $S1 \oplus S2$
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In a class of $80$ students, $40$ are girls and $40$ are boys. Also, exactly $50$ students wear glasses. Then the set of all possible numbers of boys without glasses is $\{0, \dots , 30\}$ $\{10, \dots , 30\}$ $\{0, \dots , 40\}$ none of these
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Consider the following logic circuit whose inputs are functions $f_1, f_2, f_3$ and output is $f$ Given that $f_1(x,y,z) = \Sigma (0,1,3,5)$ $f_2(x,y,z) = \Sigma (6,7),$ and $f(x,y,z) = \Sigma (1,4,5).$ $f_3$ is $\Sigma (1,4,5)$ $\Sigma (6,7)$ $\Sigma (0,1,3,5)$ None of the above
12
Express the function $f(x,y,z) = xy' + yz'$ with only one complement operation and one or more AND/OR operations. Draw the logic circuit implementing the expression obtained, using a single NOT gate and one or more AND/OR gates. Transform the following logic circuit (without expressing its switching function) into an equivalent logic circuit that employs only $6$ NAND gates each with $2$-inputs.
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An operating system used Shortest Remaining System Time first (SRT) process scheduling algorithm. Consider the arrival times and execution times for the following processes: ... $P2$ ? $5$ $15$ $40$ $55$
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Consider a logic circuit shown in figure below. The functions $f_1, f_2 \text{ and } f$ (in canonical sum of products form in decimal notation) are : $f_1 (w, x, y, z) = \sum 8, 9, 10$ $f_2 (w, x, y, z) = \sum 7, 8, 12, 13, 14, 15$ $f (w, x, y, z) = \sum 8, 9$ The function $f_3$ is $\sum 9, 10$ $\sum 9$ $\sum 1, 8, 9$ $\sum 8, 10, 15$
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Analyse the circuit in Fig below and complete the following table ${\begin{array}{|c|c|c|}\hline \textbf{a}& \textbf{b}& \bf{ Q_n} \\\hline 0&0\\\ 0&1 \\ 1&0 \\ 1&1 \\ \hline \end{array}}$
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A Boolean function $f$ is to be realized only by $NOR$ gates. Its $K-map$ is given below: The realization is
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The overlay tree for a program is as shown below: What will be the size of the partition (in physical memory) required to load (and run) this program? $\text{12 KB}$ $\text{14 KB}$ $\text{10 KB}$ $\text{8 KB}$
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The following are some events that occur after a device controller issues an interrupt while process $L$ is under execution. P. The processor pushes the process status of $L$ onto the control stack Q. The processor finishes the execution of the current instruction ... value based on the interrupt Which of the following is the correct order in which the events above occur? QPTRS PTRSQ TRPQS QTPRS
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Write the adjacency matrix representation of the graph given in below figure.
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Suppose we run Dijkstra’s single source shortest path algorithm on the following edge-weighted directed graph with vertex $P$ as the source. In what order do the nodes get included into the set of vertices for which the shortest path distances are finalized? $P,Q,R,S,T,U$ $P,Q,R,U,S,T$ $P,Q,R,U,T,S$ $P,Q,T,R,U,S$
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https://gateoverflow.in/968/gate2003-85 How in the above question the functional dependency (date of birth -> age) is a partial functional dependency. (As told in the selected answer for this question) Because according to navathe the definition of partial functional dependency is A functional ... removed from X and the dependency still holds; that is, for some A belongs to X (X - {A}) -> Y.
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One needs to choose six real numbers $x_1,x_2,....,x_6$ such that the product of any five of them is equal to other number. The number of such choices is $3$ $33$ $63$ $93$
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$P$ and $Q$ are two propositions. Which of the following logical expressions are equivalent? $P ∨ \neg Q$ $\neg(\neg P ∧ Q)$ $(P ∧ Q) ∨ (P ∧ \neg Q) ∨ (\neg P ∧ \neg Q)$ $(P ∧ Q) ∨ (P ∧ \neg Q) ∨ (\neg P ∧ Q)$ Only I and II Only I, II and III Only I, II and IV All of I, II, III and IV
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Consider the following propositional statements: $P_1: ((A ∧ B) → C)) ≡ ((A → C) ∧ (B → C))$ $P_2: ((A ∨ B) → C)) ≡ ((A → C) ∨ (B → C))$ Which one of the following is true? $P_1$ is a tautology, but not $P_2$ $P_2$ is a tautology, but not $P_1$ $P_1$ and $P_2$ are both tautologies Both $P_1$ and $P_2$ are not tautologies
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Let $p, q, r$ and $s$ be four primitive statements. Consider the following arguments: $P: [(¬p\vee q) ∧ (r → s) ∧ (p \vee r)] → (¬s → q)$ $Q: [(¬p ∧q) ∧ [q → (p → r)]] → ¬r$ $R: [[(q ∧ r) → p] ∧ (¬q \vee p)] → r$ $S: [p ∧ (p → r) ∧ (q \vee ¬ r)] → q$ Which of the above arguments are valid? $P$ and $Q$ only $P$ and $R$ only $P$ and $S$ only $P, Q, R$ and $S$
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At the end of year $1998$, Shepard bought nine dozen goats. Henceforth, every year he added $p\%$ of the goats at the beginning of the year and sold $q\%$ of the goats at the end of the year where $p>0$ and $q>0$. If Shepard had nine dozen goats at the end of year $2002$, after making the sales for that year, which of the following is true? $p = q$ $p < q$ $p > q$ $p = \dfrac{q}{2}$
An IP machine $Q$ has a path to another $IP\ machine\ H$ via three $IP\ routers \ R1, R2,$ and $R3$. $Q-R1-R2-R3-H$ $H$ acts as an $HTTP\ server$, and $Q$ connects to $H$ via $HTTP$ and downloads a file. Session layer encryption is used, with $DES$ as the shared ... and $I4$ can an intruder learn through sniffing at $R2$ alone? Only $I1$ and $I2$ Only $I1$ Only $I2$ and $I3$ Only $I3$ and $I4$
Suppose $n$ processes, $P_1, \dots P_n$ share $m$ identical resource units, which can be reserved and released one at a time. The maximum resource requirement of process $P_i$ is $s_i$, where $s_i > 0$. Which one of the following is a sufficient condition for ensuring that deadlock does not occur? ... $\displaystyle{\sum_{i=1}^n} \: s_i < (m+n)$ $\displaystyle{\sum_{i=1}^n} \: s_i < (m \times n)$