In the field of , psychologists, biologists, and medical researchers combine their expertise to study the effects of the psychological factors on the immune system.

Psychoneuroimmunology

Explanation:

The field of Psychoneuroimmunology is a multidisciplinary science that involves psychologists, biologists and neurologists (or medical researchers) who study the interaction between psychological processes and both the immune and nervous systems. One of the main goals of this field is to understand how some psychological processes (such as stress) can affect our body and our immune system.

Therefore, we can see that in the field of Psychoneuroimmunology, psychologists, biologists, and medical researchers combine their expertise to study the effects of the psychological factors on the immune system.

explanation:

with the profits from the european sales, merchants purchased europe's manufactured  goods, including tools and weapons. then the merchants shipped those manufactured  goods, along with the  american  sugar and rum, to west africa where they were bartered for  slaves.