When law-abiding citizens carry concealed weapons, they are better able to defend themselves against criminal attack. This is the of concealed carry. When law-abiding citizens carry concealed weapons, criminals are also less likely to attack all citizens because they cannot tell who is carrying a gun. This is the of concealed carry.

Private benefit; external benefit

Explanation:

Citizens are faced with divers scenario where they have been threatened by guns, the gunmen understand that in some of those scenario they victims where unarmed and other scenario they are armed. When law abiding citizens carry gun to protect themselves from this gunmen it is understood to be a Private benefit of concealed carrying while this also reduces the ability of the criminals to attack them, this is known as external benefit of concealed carry.

an aneroid barometer is different from a mercury barometer in that it provides readings that increase as air pressure increases.

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