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Class work: Chapter 7 1. Suppose that the following instructions are found at the given locations in memory 20 LDA 50 21 ADD 51 50 724 51 006 a. Show the contents of IR, the PC, The MAR, the MDR and A at the conclusion of instruction 20 b. Show the contents of each register as each step of the fetch-execute cycle for instruction 21 2. One large modern computer has a 48 bit memory address register. How much Memory can the computer address. 3. Why are the two different registers MAR and MDR associated with memory? What are their equivalent s in LPC? memory or RAM as main memory. Why