1. Find the propagation delay for this circuit:
2. Find the propagation delay for this circuit:
3. Find the propagation delay for this circuit:
4. Find the propagation delay for each input/output combination in this circuit assuming all gates have a propagation delay of 10. (You will have six answers):

   Input	Sum	Cout
   A
   B
   Cin

5. Find the propagation delay for this circuit (just one answer this time):
6. Now find the propagation delay for an 8-bit ripple carry adder built following this pattern.
7. For each addition problem below, how long before the output is stable (i.e., how long before none of the output pins change values)?
   1. 00000000 + 00000001
   2. 00000010 + 00000001
   3. 00000011 + 00000001
   4. 00000000 + 00000000
   5. 11111111 + 00000001
   6. 11111110 + 00000001
8. If you connect the full adders as shown here, will the circuit still produce the correct answer? If so, why. If not, give an example of inputs that produce an incorrect output.
9. What is the propagation delay of the circuit from the previous problem?
10. Why does changing the order if the inputs affect propagation delay?

Updated Tuesday, 26 August 2025, 10:14 AM