To have a(n) is to judge a person before you know him.

Eating right and exercising daily

Ican only answer your first question, a machine is like a human body because it's a little similar. they both almost work like the same.

Push up require upper body strength, so weight-training exercises such as shoulder press, curl ups and dead lifts would improve your ability to perform proper push ups.

Personality is a mixture of characteristics/qualities that form an individual's distinctive persona. it can be influenced by environmental and biological factors; one's culture is a most important factor that shape personality. extreme mood swings, unstable relationships, distorted self-image, impulsive/risky behavior, explosive anger, chronic feelings of sadness/emptiness, etc. these could indicate that someone could have a personality disorder.