Test: Water - 1

As solids are measured in kilograms, in the same way liquids are measured in litres. For example, 1 litre of water or 3 litres of milk.

The phenomenon of remaining on the surface of a liquid without sinking is called floatation.

As boat floats, in the same way a rock sinks.

Ducks, crocodiles and seals are all amphibious and can live on both land and water whereas fishes are odd one out who live only in aquatic environment.

Stagnant water is more prevalent in the rainy season as the water from the rains gets collected in the pits and potholes and does not get drained thus remaining at one place and becoming a breeding ground for insects.

Springs is the odd one out as it is a groundwater source of water whereas rivers, lakes and reservoirs are all surface-water sources of water.

Aquatic plants are also known as hydrophytes. 'Hydro' means water and 'phytes' means plants.

Mosquitoes and other insects breed profusely in stagnant water that is not flowing. Mosquitoes lay their larvae in them which grow to form the infected malaria causing mosquitoes.

A is the correct option.In earlier times, water was not as easily available as it is available today.

The water kept in an earthen pot remain cool even in summer because earthen pot has many small holes. Water seeps out through them and evaporates from the surface of the pot. The energy needed for evaporation is taken from the water kept in the earthen pot. As a result, water kept in earthen pot become cool.

The correct option is Option B. 
Surface water includes the lakes, reservoirs (human-made lakes), ponds, streams (of all sizes, from large rivers to small creeks), canals (human-made lakes and streams), and freshwater wetlands. The definition of freshwater is water containing less than 1,000 milligrams per liter of dissolved solids, most often salt.

A waterwheel is a machine that converts the energy of free-flowing water into useful forms of power.

 Water is called a universal solvent.

Petrol, wax and kerosene are not soluble in water. Juices are soluble in water.

Malaria is a mosquito-borne infectious disease affecting humans and other animals caused by Plasmodium species. Symptoms include headache, fever, shivering, joint pain (arthritis), vomiting, hemolytic anaemia, jaundice, haemoglobin in the urine, retinal damage, and convulsions. The disease is most commonly transmitted by an infected female Anopheles mosquito.

Animals that are capable of living on both land as well as water are called amphibians.

Earthenware pots keep the water cool so that thirsty travelers can have cold water.

Water spinach, Indian lotus, water caltrop are all aquatic plants which are used by humans as a food source.