STA question 1

Suppose we are building the following circuit using only three components:

• Inverter: tcd = 0.5ns, tpd = 1.0ns, tr = tf = 0.7ns
• 2-input NAND: tcd = 0.5ns, tpd = 2.0ns, tr = tf = 1.2ns
• 2-input NOR: tcd = 0.5ns, tpd = 2.0ns, tr = tf = 1.2ns

What is tpd (Propagation delay) for this circuit?
What is tcd (Contamination delay) for this circuit?
What is tpd of the fastest equivalent circuit built using only above 3 components?

Hint:
tpd - Max. cumulative propagation delay considering all path b/w input and output.
tcd - Min. cumulative contamination delay.