3 page paper in APA format with reference list

I had to pick two Human Service Proffesions that appealed to me, which were a trauma therapist and Behavior analyst. Next I have to write a paper addressing the following:

• define what a trauma therapist and Behavior analyst are. In your definitions, make sure to describe the scope and purpose
  of human services within each profession.
• Explain
  the roles and responsibilities of the human services professionals in
  each of the two professions and where in your community these roles
  might be available.
• Finally,
  explain why these two professions appeal to you, noting specific
  attributes, characteristics, responsibilities, etc., that attract you to
  these positions.

I am having a complete block. This is as far as I got and I am unsure wither this is even correct.

trauma therapist- I enjoy helping
people and would find great pleasure in assisting clients overcoming past traumas.

Scope- conduct
assessments of clients, design treatment plans, evaluate treatment results for
the client and make changes to the plan as needed.

Purpose- to reduce or eliminate symptoms of
trauma and enhance rehabilitation to
prior level of functioning.

Availability– 
Battered women shelters, Intensive outpatient providers, Hospitals,
rehabilitation centers, and medical
centers

Behavior Analyst- would enjoy
implementing positive behavioral interventions

Scope – conduct studies that
measure influences on behaviors displayed by individuals, assist individuals in
identifying their needs and formulating treatment plans to manage problematic
behaviors, monitor individuals’ progress and collaborate with natural supports
and other care providers to provide client with most effective long term
treatment

Purpose- To identify and address
problematic behaviors in individuals

Availability- schools, correctional
institutions, psychiatric hospitals, Intensive Outpatient providers