Up to percent of body heat can be lost through the head. a. 25 b. 30 c. 50 d. 75

Well it should be 40-45% so all of those are wrong unless it's a different learning curriculum that I don't know. 

Depression is lifelong, though you can get medication to with it. the difference between sadness and depression is that sadness lasts a little bit, depression last a long time and it goes on and off. people usually get depression through experiences they have been through, or genetics.