Im what is the value of c? assume that the line is tangent to the circle a.140 b.190 c.220 d.250

Use the tangent-chord theorem:
The included chord-tangent angle is half the size of the intercepted arc.

The intercepted arc is "c".
The included chord-tangent-angle is the supplement of 110=70 degrees.
Therefore from the tangent-chord theorem, 70 degrees = half the size of arc "c"
=>
arc "c" = 2*intercepted angle = 2*70 degrees = 140 degrees.

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