If 10 percent of your day is
spent studying, how many
hours do you devote to
studying? use 24 hours as
the length of a day.

< 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⭐

do your own work and don"t cheat.

step-by-step explanation: