Please help I will give brainiest I need your help

Step-by-step explanation:

∠OAB is 90 degrees, tangent and a radius met at 90 degree angle

∠OCB=90 degrees, tan and radius meet at 90 degrees angle

OB=12

find angle BOC:

triangle BOA is right angle triangle:

cos(AOB)=adj/hyp=7/12=54.33

angle B= 180-(90+54.33)=35.67

angle COB=54.33 equal to angle AOB

angle AOC=54.33+54.33=108.66

the sum of angles of circle =360

360-108.66= 251.34( exterior angle at the center AOC)

length of the arc= angle (251.34 degrees*7)

convert degrees to radians=4.386 (251.34/π)

length=r*angle in radian=4.386*7=30.71

( i hope this is the answer)

15%

step-by-step explanation:

use the table and count the number of guesses that has two correct answers.

the following are two correct answers

10010, 01100, 11000

a total of 3 numbers having 2 correct guesses out of 20 questions.

probability of getting 2 correct guesses = the number of questions getting 2 correct answers / total number of questions.

= 3/20

to convert it into percent multiply by 100, we get

= 3/20 * 100

= 15%

the answer is 15%

you.