Questions

Tractor was the single most important invention to farmers.

Ahmadullah Shah Madrasi alias Danka Shah (1789-1858), a descendant of the Qutub Shahi family of the Deccan, was in Faizabad when the sepoys mutinied in Meerut. He threw himself into the movement then and there. This was why he also came to be known as Ahmadullah Shah Faizabadi.

No work done as there is no external external pressure in free expansion. 

Hence, Work done in a free expansion process is Zero.

Air contains water in a gaseous form called water vapour.

The Asia Pacific Summit 2018 began in Kathmandu, Nepal.

The statement "A communist government is led by one political party" is what best defiines a communist government. Here in this type of government, the power is in the hands of the one political party and it only controls the political and economic systems of the country/state.