AB = AC,
∴∠B=∠ACB.
OC = OE,
∴∠OEC=∠ACB.
∴∠B=∠OEC,
∴OE∥AB.
∵AB⊥GF,
∴OE⊥GF.
∵ point e is on ⊙O,
∴ The straight line FG is tangent to⊙ O. 。
(2) Let the radius of ⊙O be r, then OE=r and AB = AC = 2r.
∫BF = 1,CG=2,
∴AF=2r- 1,OG=r+2,AG=2r+2.
∫OE∨AB,
∴△GOE∽△GAF,
∴OEAF=OGAG,
∴r2r? 1=r+22r+2,
The solution is r=2,
That is, the radius of ⊙O is 2.