Which feature is often used to define an era? style of art
length of time
kind of calendar
type of celebration

The style of art can be used to define an era.

An era can be described as a point in time that is characterized by the passage of long years. The kind of art that was predominant in an era can be used to describe the time.

Several eras of art that has passed includes the:

The way people dressed, and the style of music are also forms of art that can be used to define an era

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style of art

Explanation:

an era isnt a calendar its actually a new period of development, kind of like a certain time of rule. a time of celebration is more like a holiday and a length of time would be more like a year or millennia. A style of art is something that gets different and changes from time to time so there would mostly likely be an era of lets just say an anime art style if you know what i mean

hello,

  i would that it was because no matter how hard people worked everyone would be paid the same, witch it was a that the russian to rule.

have a great day

the correct answer is 50.