Final answer:
The 'LOAD INDIRECT' instruction loads the value from a memory address indirectly pointed to by the operand's address. The values loaded for the instructions are 60 and 70 for 'LOAD INDIRECT 20' and 'LOAD INDIRECT 30' respectively, while 'LOAD INDIRECT 40' and 'LOAD INDIRECT 50' likely result in errors or undefined behavior due to the lack of specified memory locations.
Step-by-step explanation:
The question involves understanding how a one-address machine with an accumulator works, specifically with the instruction 'LOAD INDIRECT'. In such a computer, loading a value indirectly means that the instruction will use the contents of the given address as a pointer to the location of the data that should be loaded into the accumulator.(a) LOAD INDIRECT 20: This instruction will look at word 20 (which contains the value 40), interpret that as an address, and then load the value from word 40 (which contains 60) into the accumulator.(b) LOAD INDIRECT 30:
This instruction will look at word 30 (which contains the value 50), interpret that as an address, and then load the value from word 50 (which contains 70) into the accumulator.(c) LOAD INDIRECT 40: This instruction will result in an error or undefined behavior, as there is no word specified at address 60 (since our list ends at word 50).(d) LOAD INDIRECT 50: This instruction will also result in an error or undefined behavior, as there is no word specified for the address contained in word 50 (which contains 70)Regarding the additional instructions:c) The complement of an instruction is a concept that usually refers to flipping all the bits in a binary number, but in terms of the operation here, it may not apply directly.(d) Entry 30 means the content at the memory address 30, which in this case holds the value of 50, acting as a pointer to another memory location for the indirect loading.