1. Explain the North/South bridge bus architecture and the components connected (2 M) 2. Construct a 1024K32 memory from a 256K16 pieces. Show all the connections and calculations clearly in the solution. (6 M) 3. Why are cache memories used ?. Explain the direct mapping technique using main memory of 64 blocks and cache memory of 4 blocks. How does thrashing happen in direct mapping(4 M) 4. Define parallel processing. Explain MIMD multiprocessor systems (3 M)