The spine is the one that keeps a huminss body mantaned
Answer:
Explanation:
Given
Wheels are rotating with constant angular velocity let say 
Presence of constant angular velocity show that there is no angular acceleration thus there is no tangential acceleration.
But any particle on the rim will experience a constant acceleration towards center called centripetal acceleration.
(a) yes, there will be tangential velocity which is given by

where r=radial distance from center
(b)tangential acceleration
there would be no tangential acceleration as velocity is constant
(c)centripetal acceleration
Yes, there will be centripetal acceleration given by

They are called stem cells. This cells are undifferentiated which means it can specialize in other types when it receives the right stimuli. They can divide through mitoses and become more stem cell or become a bone, muscle, blood cell, etc.
They can have 2 origins: embryos or some human tissue; their function is to regenerate or substitute damaged cells