can some one write the reason for why external or internal?
that depends on the wedgie giver
No. There are some psychedelic drugs that can mimic schizophrenia, but there is no known external cause.
Overuse.
light green
All the external struggles in stopping the sun are the reduction of gaseous emissions that cause ozone depletion.
Yes. an external fuel pump can get hot enough to cause vapor lock on a 1990 ford e 150 v8 5.0L.
While this question should be recategorized because external stimuli do not cause the mutations that result in hemophilia, there are many types of radiation that can cause gene mutations as well as chemical exposure. For example sun light is UV light radiation wich can cause mutations (for example the mutations that result in skin cancer).
Ill health. Marital problems Bereavement
Skin rashes are one external symptom of typhus (Rickettsia) infection.
Ill health. Marital problems Bereavement
Because of Newton's First Law of Motion.