Jack has recurrent and unexpected panic attacks. He is worried about when his next panic attack will occur. This is an example of what type of disorder:

What is the leading cause of infant mortality and at what age are infants most vulnerable?

What will be an ideal response?

Statistical tests require both a(n) _____ and a(n) _____ hypothesis

a. null; alternative b. primary; secondary c. empirical; theoretical d. conceptual; testable