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Describe briefly the terms volatile and non-volatile in the context of semiconductor memory devices. Identify which of the following memories are non-volatile? A block diagram of an SRAM memory device is shown below. Its data bus (Dis/ Dour is 16-bit wide. a) Determine the density of this memory device in terms of bits in total. b) How many devices of the same memory device would be required to build a memory bank of size 819264 bits