We know that:

is an equation of a circle.
When we substitute x and y (from the pairs we have), we'll get a system of equations:

and all we have to do is solve it for a, b and r.
There will be:

From equations (II) and (III) we have:

and from (I) and (II):

Now we can easly calculate a and b:

Finally we calculate

:

And the equation of the circle is:
Answer:
a=61°
Step-by-step explanation:
a= 180° - 90° - 29°
a = 61°
The answer is 1000 because 62x4= 248 and then you take 248 and multiply it by 4 and you get 992 then you have to multiply 4x2 which is 8 and then when you add 992+8, you would get 100 ;)
It looks like the options are missing something, but based on what I can see it looks like
<span>D.She could divide 9.42 by to find the radius, then multiply 9.42 by the radius.</span>