(a) A machine instruction SWAP(R, x) interchanges the contents of the register R and the memory location x in one instruction cycle. Implement the Pb and Vb operations on binary semaphore using SWAP. (b) A machine instruction Test-Set-Branch, TSB(x, L), where x is a memory location and Lis a branch label, performs the following function in one instruction cycle: if (x == 0) branch to L else x = 0 Implement the Pb and Vb operations on binary semaphore using TSB.

Jenny wants to look at row 345 and compare it to row 17. what can she do if she wanted to easily adjust to see both at once?

Meenu wants to create a high quality drawing in a variety of colours. which device should she use for the same?

Suppose there is a relation r(a, b, c) with a b+-tree index with search keys (a, b).1. what is the worst-case cost of finding records satisfying 10 < a < 50 using this index, in terms of the number of records n1, retrieved and the height h of the tree? 2. what is the worst-case cost of finding records satisfying 10 < a < 50 and 5 < b < 10 using this index, in terms of the number of records n2 that satisfy this selection, as well as n1 and h defined above? 3. under what conditions on n1 and n2, would the index be an efficient way of finding records satisfying the condition from part (2)?