6) A computer is available without a program counter (PC). Instead, all instructions contain three parts: an operation code, an address of an operand, and the address of the next instruction. The operation code consists of 6 bits and the computer has a memory unit of 8192 words. a) b) c) How many bits must be in a memory word if an instruction is stored in one word? Show the instruction word format. What other register is needed in the control unit besides an operation register? List the micro-operations for the instruction fetch cycle of this computer. Use any register specified in part (b). I