PLEASE ANSWER QUICK!Kierran is trying to find the circumference of a circle. He knows that the radius (r) of the circle is 6 feet and that the diameter, d=2r. Which formula should he use? A) A=3.14(2r)^2
B) C=3.14(2r)
C) A=3.14d^3
D) C=3.14(2D)

Given the system of equations presented here: 2x + 4y = 14 4x + y = 20 which of the following actions creates an equivalent system such that, when combined with the other equation, one of the variables is eliminated? multiply the second equation by â’4 to get â’16x â’ 4y = â’80 multiply the second equation by â’1 to get â’4x â’ y = â’20 multiply the first equation by 2 to get 4x + 8y = 28 multiply the first equation by â’1 to get â’2x â’ 4y = â’14