Greg classified some substances as shown in the table. greg's table soluble in water insoluble in water dishwashing detergent cloth drink mix plastic sand copper why is greg's table incorrect? plastic is soluble in water. copper is soluble in water. sand is insoluble in water. drink mix is insoluble in water.

Greg’s table is incorrect because sand is insoluble in water.

on passing the small ampere of electric current through the tube made of ar and hg of cfl generates uv rays which excites the fluorescent and thus emits the high radiation by consumption of just 5- 12 w in comparison to incandescent light which requires more power such as around 40 - 55 w to lighten.

moreover the life span of fluorescent or cfl is around 8000 h whereas the life span of incandescent is around 1200 h

hence, the building installed with incandescent lights bears more electricity bill.