Answer: 4.6
Step-by-step explanation:
GH is equal to 4.6 since it is congruent to JH. GJ is one line, which makes angles GKH and JKH supplementary angles. Since angle GKH = 90, angle JKH must also equal 90, making these triangles similar. However, if you wish to see it done out mathematically, the following explanation is there:

3.6^2 + HK^2 = 4.6^2
HK^2 = 4.6^2 - 3.6^2
HK^2 = 8.2
HK = 2.86
HK^2 + GK^2 = GH^2
8.2 + 12.96 = GH^2
GH = 4.6
Answer:
I think is scalene and acute
I think you know this but just in case you dont the radius is half of the diameter. That's why I put 5 instead of 10. :)
So add all of them and then see smallest one sorry if I'm wrong
I think it is the first option. hope this helps :)