When using a compass to explore an area why do you need to know an area magnetic declination?

Magnetic declination is the angle between magnetic north (the direction the north end of a compass needle points) and true north. The declination is positive when the magnetic north is east of true north. The term magnetic variation is a synonym, and is more often used in navigation. Isogonic lines are where the declination has the same value

Kindly check the explanation section.

Explanation:

Without mincing words let's dive straight into the solution to the question.

The instructions given in the question above is very important as it concerns the total adsorption of the product on the silica gel. The instruction is made so that adsorption of the product is on the silica gel so as to avoid the distortion in polarity of the compound.

Part B.

If the student avoid the step, there would be problem of which the compound which is in mixture will be running out of the column. Also, the compounds won't be made pure.

In summary, for the first part adsorption is done on the silica gel thus, the instructions is to be followed.

For the second part, if the step is not avoided then the Compounds will be made pure if the step