Which of the following statements is not correct about cholesterol ? a. it is an essential component of cell membranes b. it is soluble in polar solvents c. it is soluble in non-polar solvents d. it is the precursor of steroid hormones

B. it is soluble in polar solvents

Explanation:

Cholesterol  are essentially found in animal cell membrane and not in plants. Generally, cholesterol are known to be non polar therefore they find it hard to dissolve in polar solvents.

A molecule is said to be polar if it possess dual charge ion that is a positive charge and a negative charge .Example of polar molecules is water, the hydrogen ion provide for the positive charge while the oxygen ion provide for the negative charges which revolves around the nuclei.

A non polar molecule has no negative or positive charge . This means that the charges are evenly distributed.

Non polar and polar molecule tends to repel each other when they miss. Since  cholesterol is non polar it lack the ability to dissolve or become soluble in polar solvent like water.

answerleaving cheese out to get moldy;

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.