Solar Radiation and Energy

Carbon dioxide is a greenhouse gas that absorbs infrared radiation from the sun and traps heat in Earth's atmosphere, causing the greenhouse effect and increasing global temperatures. Oxygen, noble gases, and nitrogen do not have significant infrared-absorbing properties like CO2 does.

Sun is a huge sphere of hot gases with a very high temperature and is a source of all the heat and light energy on earth.

Sunflower is a C₄ plant and is able to photosynthesise in high light intensity and excessive heat. They keep their stomata partially closed and are able to absorb carbon dioxide of as low a concentration as 2ppm. Hence, their productivity is higher than C₃ plants.

This is the correct answer as all statements are correct.

Water can get evaporated easily if direct sunlight is provided to the water body, but if water is present in the shade, where there are no direct sun rays falling, warm air is required to heat the water so as to evaporate it into vapours.

Sun, stars and fireflies are the examples of natural sources of light and also the luminous object. Moon is also a natural source of light through it is non-luminous. Electric bulb, torch streetlight and candle are not natural object as they are being industrially prepared but as they emit their own light so are known as artificial source of light.

Sun, stars and fireflies are the examples of natural sources of light and also the luminous object. Moon is also a natural source of light through it is non-luminous. Electric bulb, torch streetlight and candle are not natural object as they are being industrially prepared but as they emit their own light so are known as artificial source of light. So it is the moon which is a natural source of light.

 The sun is composed primarily of the chemical elements hydrogen and helium. They account for 74.9% and 23.8% of the mass of the Sun in the photosphere, respectively. All heavier elements, called metals in astronomy, account for less than 2% of the mass. The most abundant metals are oxygen (roughly 1% of the Sun's mass), carbon (0.3%), neon (0.2%), and iron (0.2%).

1 only

This is the correct option. Sun is the ultimate source of energy for all living organisms. In plants, solar energy is captured by the leaves and stored in the form of food. 

The Sun's energy is produced by nuclear fusion of light nuclei - specifically, hydrogen nuclei (protons) fusing to form helium in the core. This process releases enormous energy because the mass of helium produced is slightly less than the mass of four hydrogen nuclei, with the difference converted to energy (E=mc²).

Source of energy in an ecosystem is the sun. 

The Sun creates energy through nuclear fusion, where hydrogen nuclei combine to form helium, releasing enormous energy. Nuclear fission splits atoms and is used in power plants on Earth. Conduction and radiation are heat transfer methods, not energy production processes.

Correct option is (3).