For brainiest:):):):):):):)

8. Yes

9. No

12. No

13. Yes

Step-by-step explanation:

all angles in quadratics must be equal to 360 degrees

answer: x

step-by-step explanation:

< coa = 150 ( given)

as ba and bc are tangents

so oc and oa is perpendicular to cb and ab respectively because in circle normal passes through centre

so in quadrilateral oabc

< coa + < oab + < ocb + < abc = 360

150 +90+90 + < abc = 360

330 + < abc = 360

< abc = 360 -330 = 30

so < abc = 30

⭐dhruv⭐