-3, -2,-1, 0, 1, 2, 3, are called

Integers

Step-by-step explanation: To help introduce the set

of integers, let's use the number line shown below.

Notice that on a number line, 0 is in the middle, all numbers to the

left of 0 are negative, and all numbers to the right of 0 are positive.

The set of integers includes the set of whole numbers, {0, 1, 2, 3, ...},

which appear at 0 and to the right of 0 on the number line.

The set of integers also includes {-1, -2, -3, ...} which

appear to the left of 0 on the number line.

So the ste of integers can be written as {...-3, -2, -1, 0, 1, 2, 3...}.

< 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⭐