8. You are given an empty jar, with a mass of 40 g. If you fill the jar with water, its
mass is 140 g. If you pour the water out, and fill it with vegetable oil, the mass of
the jar of oil is 130 g. What is the density of the oil?

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.