Answer:
No of white balls = 5
Step-by-step explanation:
Given that,
Total no of red balls = 4
Total no of green balls = 6
The probability of not drawing a white ball in one draw be, 
We need to find the number of white balls. Let there are x balls.
The probability of drawing a white ball = 1 - the probability of not drawing a white ball
= 1 -2/3
= 1/3
Using the formula for solving probability of having a white ball.

Hence, there are 5 white balls.
Answer:
Step-by-step explanation:
<u><em>Part B:</em></u>
The center of the circumscribed circle around a triangle is equidistant from vertices of that triangle. To find the circumcenter need to draw at least two perpendicular bisectors to the sides of the given triangle. Point of intersect of them is center of the circumscribed circle.
<u><em>Part C:</em></u>
Coordinates of the midpoint of line BC ( y = - 1 ) are
(
,
) = <em>( - 2 , - 1 )</em> and the equation of the line ⊥ to BC is <em>x = - 2</em>
Because BC is ║ to x-axis and m∠A is 90° , the center of the circle is midpoint of BC and r =
= 4