Why must the senate approve the presidents choices for the supreme court?

Why are the majority of the world's economies mixed? what may happen to the "pure" types of economies (traditional, socialist/command, market capitalist) when they incorporate elements from other economic models?

What is the best definition of economic data?

Atherapist at a free university clinic treats elementary school children with behavior problems who are referred by a social service agency. she is also a doctoral candidate who proposes using data she has and will collect about the children for a case-based research project. describe the type of parental permission which is required in this case?