Answer:
Part 1)

Part 2)

Part 3)

Explanation:
step 1
Find the length HD
In the right triangle HDF
Applying the Pythagoras Theorem

substitute the values and solve for HD




step 2
Find the length JD
In the right triangle JDF
Applying the Pythagoras Theorem

we have

----> because JD is a perpendicular bisector
substitute the values and solve for JD





step 3
Find the length KD
In the right triangle KDG
Applying the Pythagoras Theorem

we have

substitute the values and solve for KD




