What is the angle of depression at which Chris is looking?

Question

Finding angle of depression but I don't have idea of what I should mark as hypotenuse or opposite? Please help!

So, here is the question:

Chris is standing on the top of the cliff of 70 m and sees a ocean 180 m from where he is standing. What is the angle of depression at which he is looking?

Answer 1

HUGE HINT:

the angle between the horizontal and the observer's line of sight is called the angle of depression

Diagram with hint as requested

Hopefully, that helps :)