Question: A hardware stack is used to evaluate arithmetic expressions. The expressions can contain both REAL and INTEGER values. The data representation contains a TAG bit with each operand. The TAG bit is 1 for REAL and 0 for INTEGER data. List the control signals needed for the stack-based ALU of Figure to perform addition and subtraction of the operands in the top two levels of the stack. Include any additional hardware needed to accommodate this new data representation.
