12 1/2 - 3v for v = -5 in distributive property form

< 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⭐

(hint): the answer is in the question.

they r 125, and 216

so the sequence goes 1,8,27,64,125,216