Global warming takes place due to increase of which gas in air?
Carbon monoxide
Carbon dioxide
Ammonia
Oxygen
Which of the following gases is not a green house gas?
Sulphur dioxide
Methane
Glass panel usually appear hazy because
Water vapour settles on the tiny dust particles.
It is the property of transparent substance
The glass is old
Of chemical reactions
Plankton are micro organisms that live in water bodies such as seas and ponds. They feed on other aquatic micro organisms that make food using sunlight. An oil spill has occurred on the sea near the south of Singapore.
Which one of the following graphs shows the population of plankton in the area affected by the oil spill?
Electric wires are usually made of
Aluminium
Magnesium
Copper
Silver
In an area 'X', there is a factory that burn fuels for energy and causes air pollution. The smoke that it produces contain dust, soot and other harmful gases.
Which of the following is the best solution?
Factories should be built in areas where few people live.
People who live near factories must be prepared to breathe in polluted air.
Lot of trees should be planted near factories to absorb hamrful gases.
Factories should have large chimneys and special device to remove pollutants from smoke.