What will you do to determine the right quantity of the materials needed

Analyse the material required to build the instrument gauge and then keep a buffer stock of 1%

Explanation:

The right quantity to buy differs for every material. There are some materials which are very expensive and are very less used than buffer stock for such materials cannot be purchased. Usually the buffer is to be on the safe side from the shortage of the material. The buffer stock kept is around 1 to 2% for metal materials.

it doesn't. it was imagined up in the middle ages.