Which of the following statements about clustering are correct?

	1.	In order to perform cluster analysis, we need to have a similarity measure between data objects.
	2.	When clustering, we want to put two dissimilar data objects into the same cluster.
	3.	We need to be able to handle a mixture of different types of attributes (e.g., numerical, categorical).
	4.	The choice of an appropriate metric will influence the shape of the clusters.
	5.	We must know the number of clusters a priori for all clustering algorithms.
	6.	Clustering analysis is unsupervised learning since it does not require labeled training data.
	7.	Graphs, time-series data, text, and multimedia data are all examples of data types on which cluster analysis can be performed.