use pic 5 for all questions
4. Given: mBD = 45 degrees, AF = 6
mCD =
A. 45°
B. 90°
C. 225°
D. 135°

because a radius perpendicular to a chord bisects the chord and its subtended arc.
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5. same as question 4
m<BAD =
A. 60°
B. 35°
C. 30°
D. 45°

because the measure of a central angle is equal to the measure of its subtended arc.
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6. Same as question 4.
BF = ?
A. 3 *2 (2 is squared = *)
B. 3 *3
C. 2 *3
D. 6

because

is isosceles.