Heeelp

Step-by-step explanation:

Xét ∆ABC có:

C= 180-30-45=105°

D= 180-105-45÷2= 75-22,5= 52,5°

11 feet 6 inches and 8 feet 6 inches

< 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⭐