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A 2Q buffer replacement policy is managing a 3-frame buffer pool. The current state of the queues is: LRU Queue (ordered least recently used first → most recently used last): {1} FIFO Queue (ordered oldest inserted first → newest inserted last): {2} The next page reference is 2.   What will be the new state of the queues after this access?  

A 2Q buffer replacement policy is managing a 3-frame buffer pool. The current state of the queues is: LRU Queue (ordered least recently used first → most recently used last): {1, 2} FIFO Queue (ordered oldest inserted first → newest inserted last): {}  The next page reference is 3.   What will be the new state of the queues after this access?  

SELECT PostID, UserID, Content, PostDate FROM Posts;   Can the output table of this query change across multiple executions?   

You are designing a data warehouse application that aggregates financial data by product, time-period, and city. Data is uploaded once per day at midnight.   What type of workload does this represent?  

What is the correct order of evaluation for relational operators in SQL?  

Can using a separate mutex for each page in a buffer pool avoid deadlocks?  

In a slotted page structure, what happens when an update increases the size of a tuple beyond its original allocated space (assume that the updated tuple is still smaller than the slotted page)?  

2Q buffer replacement policy is managing a 3-frame buffer pool. The current state of the queues is: LRU Queue (ordered least recently used first → most recently used last): {1, 2} FIFO Queue (ordered oldest inserted first → newest inserted last): {9} The next page reference is 2.   What will be the new state of the queues after this access?  

std::rand() % user_ids.size()   What is the possible output range of the following C++ expression?  

Problem 1. (15 points total) What are the different types of faults that can occur in a power system?    Problem 2. (15 points total) Describe any three applications of a phasor measurement unit (PMU).    Problem 3. (20 points total) Suppose that there is a three-bus system. The voltage phasors of the three buses are V1 = 1∠0° V, V2 = 2∠30° V, and V3 = 3∠60° V. The network has a triangular structure (i.e., all three buses are connected to each other), and all the line impedances are equal to 1 + j Ω. What is the phasor representation of the three current phasors in Cartesian coordinates?