You are a mad scientist. You have figured out a way to replace one part of the respiratory and circulatory systems. You believe by doing this one thing you can create an army of physically unbeatable warriors and conquer the world. (Remember you are MAD!) a - What part would you replace to accomplish this? b - What would you replace it with? c - Explain your thinking on how doing this would help create these powerful warriors.

I'd proceed to order pipes from ebay as to replace said parts.

During the process I'd question why is there an army of beef-cake Mega-Men in my basement.

Since I'm a mad scientist I'd make some type of body armor that enhances durability, Thus allowing my warriors to remain standing tall while taking a few rounds of a some good ol' bullet lead.

I would also use BIO-Tech enhancing their skin durability to take the deepest of cuts. Muscle definition and power so my men could slap an Elephant to next week.

(Or atleast until the government find out about the absolute units in my basement and arrest me)

a chair, a bed, and a toothbrush

explanation: