The case of a 3-arm interchange is not covered in the article's section. A special constuction can be found at the I-10 / I-20 in west Texas, also applied at some interchange constructions in Florida. This example shows how costs of flyover ramps and bridges are increased, compared to a simple at-grade ramp/road.
Counseling and therapy are generally two synonymous terms as they can be interchanged. A therapist can provide counseling and psychotherapy. However, a person who counsels called a counselor will depend on the degree he or she has received. Therapy involves a more difficult task to do compared to counseling. So the people conducting that can be psychiatrists, psychologists, or social workers.
1 A Therapist uses talking therapies to treat mental health problems. A Therapist can be a Psychiatrist, a Psychologist, a Social Worker, a Psychiatric Nurse, etc, and then has further training in using talking therapies.  A Counsellor is a therapist who uses psychodynamic techniques.