Which of the following is linear transformation?

Which of the following is linear transformation? A linear transformation (or a linear map) is a function T:Rn→Rm that satisfies the following properties: T(x+y)=T(x)+T(y)

A linear transformation (or a linear map) is a function T:Rn→Rm that satisfies the following properties: T(x+y)=T(x)+T(y)
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