To solve the problem:

Key Points from the Question:

• GH is the adjacent side.
• HK is the opposite side.
• GK is the hypotenuse.

Step-by-Step Solution:

1. Understand the Triangle:

   • The hypotenuse (GK) is always the longest side of the triangle.
   • The adjacent side (GH) is the side next to the angle being referenced but is not the hypotenuse.
   • The opposite side (HK) is the side across from the angle being referenced.

2. Identifying the Angle:

   • If GH is adjacent, HK is opposite, and GK is the hypotenuse, we are describing ∠G. This is because:
     • GH (adjacent) lies next to ∠G.
     • HK (opposite) is across from ∠G.
     • GK remains the hypotenuse for the entire triangle.

3. Conclusion:

   • Julian is describing ∠G.

Final Answer:

The correct choice is: ∠G.

Would you like additional details on trigonometric relationships or further clarification? Here are some related questions to deepen understanding:

1. How do you determine the opposite, adjacent, and hypotenuse for a given angle in any right triangle?
2. What are the sine, cosine, and tangent ratios, and how do they relate to the sides of a triangle?
3. Can this method of identifying angles and sides be applied to non-right triangles? If not, why?
4. Why is the hypotenuse always the longest side of a right triangle?
5. How would you describe the other angles (∠H and ∠K) in this triangle based on their sides?

Tip: Remember, the key to identifying angles in right triangles is correctly labeling the sides relative to the angle of interest.