Remember that there is 100 centimeters in a meter, and 1000 meters in a kilometer. If you multiply both values together (so you have a conversion of centimeters to kilometers) you get 100,000. Therefore, 100,000 centimeters makes a kilometer. Divide 320,000 by 100,000 and you get 3.2. Therefore, a centimeter would represent 3.2 kilometers.
C, see explanation in the picture attached below.
X^2+4x-12
x^2+6x-2x-12
x(x+6)-2(x+6)
(x-2)(x+6)
So, B is the answer
