Suppose we have the instruction Load 500. Given that memory and register R1 contain the values below: Address Content 600 400 300 Content R1 200 500400 700 700 800 Assuming R1 is implied in the indexed addressing mode, determine the actual value loaded into the accumulator and fill in the table below: Mode Value Loaded into AC Immediate Direct Indirect Indexed The memory unit of a computer has 1 M words of 32 bits each. The computer has an instruction format with 4 fields: an opcode field; a mode field to specify 1 of 15 addressing modes; a register address field to specify 1 of 16 registers; and a memory address field. Assume an instruction is 32 bits long. Answer the following: a. How large must the mode field be? b. How large must the register field be? c. How large must the address field be? d. How large is the opcode field