Answer: 35 degrees.
Step-by-step explanation: HF and GH are congruent to each other. That means angle F and angle G are the same as well (since those are the angles opposite the sides). If angle G is 35, angle f is also 35.
The answers are:
Diameter: 30m
Circumference: 94.24777960769379
Area: 706.8583470577 m<span>2
I hope this helps you. Good luck with your work!</span>
If you finish the question I may be able to answer it. ^^