Ricardo can type 39 words per minute. Estimate the number of words he can type in 18 minutes. 400 or 600 or 300 or 800

800

Step-by-step explanation:

ROund 39 to 40 and 18 to 20.

This results in 40 x 20=800.

< 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⭐

step-by-step explanation:

b and c