What are uses of liquid nitrogen?

It it used for lots of things like a coolant for computers, in medicine to remove unwanted skin, warts and pre-cancerous cells, and in cryogenics, in which scientists study the impact of very cold temperatures on substances.

Explanation:

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the population of unionid mussels in the hudson river decreased after zebra mussels were introduced. zebra mussels, a nonnative species, competed with the unionid mussels for food. the zebra mussels were able to outcompete the unionid mussels, allowing the zebra mussel population to increase dramatically over six years. the unionid mussel population decreased due to a lack of food.

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