The following samples are observations taken from the same elements at two different times: 
Assume that the populations are normally distributed and construct a 90% confidence interval for the difference in the means of the distribution at the times in which the samples were taken.
Definitions:
Social Relationships
Connections between individuals based on common interests, social roles, or emotional bonds, which influence behavior and social development.
Depressive Episode
A period characterized by pervasive sadness or a lack of interest in life, often with other mental and physical symptoms, defining major depressive disorder.
Aged
A term referring to individuals who are significantly older, often in the later stages of their life, typically associated with advanced age.
High Blood Pressure
A chronic medical condition in which the force of the blood against the artery walls is elevated enough that it may eventually cause health problems.
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