Questions

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A command economy types of government decide which goods would be produced without any interference of the public.

Command economy ran in Germany during the rule of Adolf Hitler. 

A command economy tends to exist under a socialist government that provides a lot of regulation.

A Jig saw puzzle pieces are in different colors which have different shapes. 

You can put it anywhere you like but there is only one right place for it to be fit in it.

Investment and asset are really close in meaning. Investment is when you put your money in stock, bond or other financial instruments. Whereas Asset is what you own generally reffered to land, proprietorship , factory, etc.

Venus is known as earth's twin because of its closeness to the earth with respect to size, mass(weight) and density.

Air pollutants are solid particles, gases, and liquid droplets in the air that can adversely affect ecosystems and the health of humans.

Major ambient air pollutants include toxic metals, polycyclic aromatic hydrocarbons, benzene, particulate matter (PM), nitrogen oxides, sulfur oxides, carbon monoxide, and ozone. Power plants, factories, and vehicle and air traffic are the most important anthropogenic sources of air pollution.

In addition, natural sources such as wildfires and volcanic activity contribute to ambient air pollution.