# Recent activity by Shashi Shekhar 1

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Suppose $Y$ is distributed uniformly in the open interval $(1,6)$. The probability that the polynomial $3x^2 +6xY+3Y+6$ has only real roots is (rounded off to $1$ decimal place) _______
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Hii , can anyone tell me what specialization to choose between CSE and MATHEMATICS AND COMPUTING? which is best keeping in mind the government jobs like ISRO,AAI,BHSPCL ETC.
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What is the minimum number of $2$-input NOR gates required to implement a $4$ -variable function expressed in sum-of-minterms form as $f=\Sigma(0,2,5,7, 8, 10, 13, 15)?$ Assume that all the inputs and their complements are available. Answer: _______
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Evaluation of the given postfix expression $10 \: 10 + 60 \: 6/^*8$- is $192$ $190$ $110$ $92$
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X is uniformly distributed random variable that takes values between 0 and 1.The value of E(X^3) will be
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For any context-free grammar there is a parser that takes at most O (n$^3$ ) time to parse a string of n terminals. True or False?
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If a grammar( $CFG$ ) has more than one Right most derivation, Can it be called ambiguous ? Or we say a grammar is ambiguous only when it has more than one left most derivation ?
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In a sliding window $ARQ$ scheme, the transmitter's window size is $N$ and the receiver's window size is $M$. The minimum number of distinct sequence numbers required to ensure correct operation of the $ARQ$ scheme is $min (M, N)$ $max (M, N)$ $M + N$ $MN$
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A relational database contains two tables Student and Performance as shown below: ... Marks) FROM Student S, Performance P WHERE P.Marks >84 GROUP BY S.Student_name; The number of rows returned by the above SQL query is ________
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What is the for the question where two statements were given as: S1: matrix A is invertible S2:|A|=0?
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You are working on a laptop connected to a $100 \text{Mbps}$ Ethernet LAN. You need a $2 \text{GB}$ file that is on the server in the same LAN. The entire file is also on your pen drive but you have left the pen drive in another room. You ... be able to go and bring the pen drive, before the transfer on the LAN completes. Assume continuous data transmission on the LAN(no packetization required)).
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Consider the following graph. How many paths of length $4$ exist from node $A$ to node $D$? (Note: The path may have repeated vertices. You can think of it as walks in general rather than path)
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what could be the eigen values of a 2*2 Matrix if all its elements are intergers.
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Suppose when there is cache “Miss” then memory Access is 30ns and when cache “Hit” then memory access time is 3ns if 80% is cache hit then effective memory access 9ns 8.4ns 3ns 9.10ns
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Which type of hazards mitigate by data forwarding war and waw both war only waw only none of above
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A hard disk system has the following parameters : Number of tracks $= 500$ Number of sectors/track $= 100$ Number of bytes /sector $= 500$ Time taken by the head to move from one track to adjacent track $= 1 \ ms$ Rotation speed $= 600 \ rpm$. What is the average time taken for transferring $250$ bytes from the disk ? $300.5 \ ms$ $255.5 \ ms$ $255 \ ms$ $300 \ ms$
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A CPU has a five-stage pipeline and runs at $1$ GHz frequency. Instruction fetch happens in the first stage of the pipeline. A conditional branch instruction computes the target address and evaluates the condition in the third stage of the pipeline. The processor stops fetching new instructions following ... is: $\text{1.0 second}$ $\text{1.2 seconds}$ $\text{1.4 seconds}$ $\text{1.6 seconds}$
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As I know that if any schedule is conflict serializable then it must be view serializable but if not conflict serializability then check for blind write if not found then not view serializable if found then check from polygraph or If a schedule S is view-equivalent to ... . then we have to make serial schedule by given schedule or what. please help if possible with help of diagram or example.
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Is there internal fragmentation in continuous dynamic partitioning ? After the processes have been allocated the partitions according to their size , there is no internal fragmentation , I agree but what if some processes have completed their execution and left leaving behind the holes of ... comes which has size smaller than the hole , then will it create a new partion of its size from the hole?
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A Binary semaphore variable mutex is initialized to '1' and the various binary semaphore operations like 9P(), 14V(), 6P(), 8V(), 3P(), 2V() are performed, then what is the present(final) value of the binary semaphore mutex?
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Define languages $L_0$ and $L_1$ as follows : $L_0 = \{\langle M, w, 0 \rangle \mid M \text{ halts on }w\}$ $L_1 = \{\langle M, w, 1 \rangle \mid M \text{ does not halts on }w\}$ Here $\langle M, w, i \rangle$ is a triplet, whose first component $M$ ... but $L'$ is not $L'$ is recursively enumerable, but $L$ is not Both $L$ and $L'$ are recursive Neither $L$ nor $L'$ is recursively enumerable
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Minimum number of 2 input nor gates required for xy+z?