Why is cholestrol important for the body

it's important because it's the structure of cell membranes also it helps your body make vitamin D

Cholesterol is important for the body because of these reasons:

It is an important factor that the body uses to build cell membrane structures.  

It is an important ingredient that creates hormones such as oestrogen, adrenal hormones, and testosterone.  

Metabolism can't work efficiently without it.  

It is an important ingredient for the body in order to produce Vitamin D. Though cholesterol is needed in the body, it does not mean that the body can benefit so much with the high level of it. Only a small amount will do. More than what is needed can already cause negative things in the body.

answer: semi-infinite solid initially at a uniform temperature of 400 ◦c is cooled at its surface by convection. the cooling fluid at a constant temperature of 200 ◦c has a convective coefficient (ha) of 250 w/m2.k. the physical properties of the solid: k = 20 w/m.k and α = 4 * 10-5  m2/s. using δx = 0.04 m and δt = 10 s. write the finite difference equations describing the transient heat transfer of the first five δx and the temperature profile after 30 s.