what is group similar objects
True. In geometry it is sometimes helpful to group objects and look at similarities between them.
combine
combine
Combine
trio
Grouping similar objects means organizing or categorizing them based on shared characteristics or qualities. This helps to make sense of large or diverse datasets and facilitates easier analysis, comparison, and identification of patterns among the objects.
match
Arrange, analyze
This is a two part question. Clustering is when you group a set of objects in a way that the objects that are placed in the same group are similar. An example of clustering is the gathering of different populations based on language.
Those are "concussion" instruments. They include cymbals and castanets.
By removing the objects you choose to subtract from the group of objects.