Questions

The air around us is a mixture of gases, mainly nitrogen and oxygen, but containing much smaller amounts of water and other gases.

Earth's atmosphere is composed of many gases. Their percentages by volume is given by::

 
78% Nitrogen,

21% Oxygen,

0.9% Argon, and

0.03% Carbon dioxide 

And very small percentages of other elements.

Garbage burning is common in rural areas, but it poses health concerns and hazards to the environment. It especially affects people with sensitive respiratory systems, as well as children and the elderly.

Benefits ::

• It produces methane that can be used like natural gas.
• It partially addresses the solid waste disposal problem.
• It provides biomass energy.

Hence, it creates more space for farming is not the benefit of the burning garbage.

Since, the starting statement carries a subject; S will be the first statement as it talked about the world’s fastest computers. The next statement describes the initial use of the same and the statement that follows states the new uses of the computers as environmental tools. Thus SQRP is the correct sequence and thus form a coherent paragraph.

The correct formation would be, ‘The world’s fastest computers initially conceived for military purposes are finding various new uses as environmental tools.

‘Abide’ means ‘to put up with’. ‘abide’ is always followed by the preposition ‘by’.

The oxygenated blood  flows through pulmonary veins then leaves the lungs, which return it to the left heart, completing the pulmonary cycle.