Computer architecture X uses variable-length instructions of several different formats, each occupying a whole number of bytes (or a number of bits...

Computer architecture X uses variable-length instructions of several different formats, each occupying a whole number of bytes (or a number of bits that is a multiple of 8).Format 1 begins with four flag bits, followed by a 0 bit, followed by an opcode and a 12-bit signed 2’s complementoffset.Format 2 begins with four flag bits, followed by bits 10, followed by an opcode, two 5-bit register fields and a 16-bit signed 2’s complement immediate operand.Format 3 begins with four flag bits, followed by bits 100, followed by an opcode, three 5-bit register fields and an 8-bit unsigned immediate operand.Format 4 begins with four flag bits, followed by bits 110, followed by an opcode, two 5-bit register fields and a 13-bit signed 2’s complement immediate operand.Assume that no opcode exceeds 8 bits.(a) Illustrate each instruction format (see Figure 9-14 for an example).(b) How many registers does the architecture X employ?(c) How many bits are used for the opcode in each of the four formats?