I have neither given nor received help on this test. You may omit any ONE question but you must indicate which one you want omitted by writing OMIT next to it and circling the question number. You may elect to do the OMITed question for extra credit. Do not spend an excessive amount of time on any one question.
All questions count the same.
If you have trouble with a question, skip it and come back to it later. Implement a 2 bit half adder by any efficient means. Inputs are X1, X0, Y1 and Y0. The half adder has no carry-in. Design a two-bit full adder using the two bit half adder and the increment circuit that you designed above.