hello, I need help with these questions. using this passage: http://www.rufusandrufus.com/attorney_client_privilege.pdf A. What qualifies a witness

hello, I need help with these questions. using this passage: http://www.rufusandrufus.com/attorney_client_privilege.pdf

A.     What qualifies a witness as an expert?

A.     Under what conditions may an expert testify in a court of law?