Proponents fear that because value-added tests don't produce individual grades, students will not take them seriously, making the results invalid or even useless.

Nor will the state tell local districts how to produce local grades.

But Brazil, which is the world's largest coffee grower and produces mainly standard grades, has not endorsed Colombia's plan.

Cuttings taken from the original plants have been used to produce similar grades of tea from genetically identical plants.

Such units are characterized by high yield per performance volume and also have the flexibility to produce different grades and/or products.

The region produces low grades of wheat and other cultures.

Its single paper machine produces several grades of supercalendered paper used for catalogs, magazines, advertising inserts and other commercial printing.

Paper machines are run with deionised or even distilled process water when producing higher grades of electrical insulation paper.

The producers can then either sell the sugar product for use as is, or process it further to produce lighter grades.

Sieving the resultant white sugar produces different grades for selling.