Answer:
it might be 3 one according to me
Answer:
The value of a is 101°, b is 79°, c is 83° and d is 97°
I'm assuming this is multiple choice and you forgot to post the answers. I'll take a guess and say it probably looks something like this:

Because you can't take the square root of a negative number without getting an imaginary result, resulting in the function having a closed domain limit.
Use a proportion.
2 adults to 18 students is as x adults to 99 students.
2/18 = x/99
18x = 2 * 99
18x = 198
x = 11
Answer: 11 adults