.
I will answer question 1 only.
Use the Theorem:
If two chords intersect in the interior of a circle, then the product the measures of the segments the intersection point
divides each chord is the same.
See the lesson - The parts of chords that intersect inside a circle in this site.
Then you have |AF|*|BF| = |EF|*|GF|, or 8*6 = 2*|EF|, which implies
|EF| = = 24 units.
Solved.
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In this site, you have this free of charge online textbook on Geometry
GEOMETRY - YOUR ONLINE TEXTBOOK
The referred lesson is the part of this online textbook under the topic "Properties of circles, inscribed angles, chords, secants and tangents ".
Save the link to this online textbook together with its description
Free of charge online textbook in GEOMETRY
https://www.algebra.com/algebra/homework/Triangles/GEOMETRY-your-online-textbook.lesson
to your archive and use it when it is needed.
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