A quadrilateral \(EFGH\) is inscribed in a circle. If \(EF\) is a diameter, what can you say about \(∠EGH\) and \(∠EFH\)? Substantiate your answer.
 
Answer:
 
The given information is pictorically illustrated as follows:
 
p_11_4.PNG
 
\(∠EGH\) and \(∠EFH\) are .
 
Reason: