Give a circuit to add/subtract two 2-bit 2's complement numbers ajao and bibo. Your circuit will have also have an input SUB, which is set to 0 if you want to add, and set to 1 if you want to subtract (ie. aa-bibo). Your circuit will have three outputs C,So and si, where C is the carry-out, So is bit 0 of the result, and si is bit 1 of the result. Finally, your circuit can ONLY use two 1-bit full adders and a few gates (AND,OR,NOT,NOR,NAND,XOR). Hint: XOR gates can be useful here