Answer:
a. 6
b. 7
c. (b) Kira's
why? b. it has the large sample size
Step-by-step explanation:
Answer:
, 
Step-by-step explanation:
Given
the equation is 
completing the square

Thus, the center of the circle is
and radius is 
-15 and -42 both add to -57 and multiply to 630